pkg/web_components/lib/platform.concat.js

/*
 * Copyright 2012 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

if (typeof WeakMap === 'undefined') {
  (function() {
    var defineProperty = Object.defineProperty;
    var counter = Date.now() % 1e9;

    var WeakMap = function() {
      this.name = '__st' + (Math.random() * 1e9 >>> 0) + (counter++ + '__');
    };

    WeakMap.prototype = {
      set: function(key, value) {
        var entry = key[this.name];
        if (entry && entry[0] === key)
          entry[1] = value;
        else
          defineProperty(key, this.name, {value: [key, value], writable: true});
      },
      get: function(key) {
        var entry;
        return (entry = key[this.name]) && entry[0] === key ?
            entry[1] : undefined;
      },
      delete: function(key) {
        this.set(key, undefined);
      }
    };

    window.WeakMap = WeakMap;
  })();
}

// Copyright 2012 Google Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

(function(global) {
  'use strict';

  // Detect and do basic sanity checking on Object/Array.observe.
  function detectObjectObserve() {
    if (typeof Object.observe !== 'function' ||
        typeof Array.observe !== 'function') {
      return false;
    }

    var records = [];

    function callback(recs) {
      records = recs;
    }

    var test = {};
    var arr = [];
    Object.observe(test, callback);
    Array.observe(arr, callback);
    test.id = 1;
    test.id = 2;
    delete test.id;
    arr.push(1, 2);
    arr.length = 0;

    Object.deliverChangeRecords(callback);
    if (records.length !== 5)
      return false;

    if (records[0].type != 'add' ||
        records[1].type != 'update' ||
        records[2].type != 'delete' ||
        records[3].type != 'splice' ||
        records[4].type != 'splice') {
      return false;
    }

    Object.unobserve(test, callback);
    Array.unobserve(arr, callback);

    return true;
  }

  var hasObserve = detectObjectObserve();

  function detectEval() {
    // don't test for eval if document has CSP securityPolicy object and we can see that
    // eval is not supported. This avoids an error message in console even when the exception
    // is caught
    if (global.document &&
        'securityPolicy' in global.document &&
        !global.document.securityPolicy.allowsEval) {
      return false;
    }

    try {
      var f = new Function('', 'return true;');
      return f();
    } catch (ex) {
      return false;
    }
  }

  var hasEval = detectEval();

  function isIndex(s) {
    return +s === s >>> 0;
  }

  function toNumber(s) {
    return +s;
  }

  function isObject(obj) {
    return obj === Object(obj);
  }

  var numberIsNaN = global.Number.isNaN || function isNaN(value) {
    return typeof value === 'number' && global.isNaN(value);
  }

  function areSameValue(left, right) {
    if (left === right)
      return left !== 0 || 1 / left === 1 / right;
    if (numberIsNaN(left) && numberIsNaN(right))
      return true;

    return left !== left && right !== right;
  }

  var createObject = ('__proto__' in {}) ?
    function(obj) { return obj; } :
    function(obj) {
      var proto = obj.__proto__;
      if (!proto)
        return obj;
      var newObject = Object.create(proto);
      Object.getOwnPropertyNames(obj).forEach(function(name) {
        Object.defineProperty(newObject, name,
                             Object.getOwnPropertyDescriptor(obj, name));
      });
      return newObject;
    };

  var identStart = '[\$_a-zA-Z]';
  var identPart = '[\$_a-zA-Z0-9]';
  var ident = identStart + '+' + identPart + '*';
  var elementIndex = '(?:[0-9]|[1-9]+[0-9]+)';
  var identOrElementIndex = '(?:' + ident + '|' + elementIndex + ')';
  var path = '(?:' + identOrElementIndex + ')(?:\\s*\\.\\s*' + identOrElementIndex + ')*';
  var pathRegExp = new RegExp('^' + path + '$');

  function isPathValid(s) {
    if (typeof s != 'string')
      return false;
    s = s.trim();

    if (s == '')
      return true;

    if (s[0] == '.')
      return false;

    return pathRegExp.test(s);
  }

  var constructorIsPrivate = {};

  function Path(s, privateToken) {
    if (privateToken !== constructorIsPrivate)
      throw Error('Use Path.get to retrieve path objects');

    if (s.trim() == '')
      return this;

    if (isIndex(s)) {
      this.push(s);
      return this;
    }

    s.split(/\s*\.\s*/).filter(function(part) {
      return part;
    }).forEach(function(part) {
      this.push(part);
    }, this);

    if (hasEval && this.length) {
      this.getValueFrom = this.compiledGetValueFromFn();
    }
  }

  // TODO(rafaelw): Make simple LRU cache
  var pathCache = {};

  function getPath(pathString) {
    if (pathString instanceof Path)
      return pathString;

    if (pathString == null)
      pathString = '';

    if (typeof pathString !== 'string')
      pathString = String(pathString);

    var path = pathCache[pathString];
    if (path)
      return path;
    if (!isPathValid(pathString))
      return invalidPath;
    var path = new Path(pathString, constructorIsPrivate);
    pathCache[pathString] = path;
    return path;
  }

  Path.get = getPath;

  Path.prototype = createObject({
    __proto__: [],
    valid: true,

    toString: function() {
      return this.join('.');
    },

    getValueFrom: function(obj, directObserver) {
      for (var i = 0; i < this.length; i++) {
        if (obj == null)
          return;
        obj = obj[this[i]];
      }
      return obj;
    },

    iterateObjects: function(obj, observe) {
      for (var i = 0; i < this.length; i++) {
        if (i)
          obj = obj[this[i - 1]];
        if (!isObject(obj))
          return;
        observe(obj);
      }
    },

    compiledGetValueFromFn: function() {
      var accessors = this.map(function(ident) {
        return isIndex(ident) ? '["' + ident + '"]' : '.' + ident;
      });

      var str = '';
      var pathString = 'obj';
      str += 'if (obj != null';
      var i = 0;
      for (; i < (this.length - 1); i++) {
        var ident = this[i];
        pathString += accessors[i];
        str += ' &&\n     ' + pathString + ' != null';
      }
      str += ')\n';

      pathString += accessors[i];

      str += '  return ' + pathString + ';\nelse\n  return undefined;';
      return new Function('obj', str);
    },

    setValueFrom: function(obj, value) {
      if (!this.length)
        return false;

      for (var i = 0; i < this.length - 1; i++) {
        if (!isObject(obj))
          return false;
        obj = obj[this[i]];
      }

      if (!isObject(obj))
        return false;

      obj[this[i]] = value;
      return true;
    }
  });

  var invalidPath = new Path('', constructorIsPrivate);
  invalidPath.valid = false;
  invalidPath.getValueFrom = invalidPath.setValueFrom = function() {};

  var MAX_DIRTY_CHECK_CYCLES = 1000;

  function dirtyCheck(observer) {
    var cycles = 0;
    while (cycles < MAX_DIRTY_CHECK_CYCLES && observer.check_()) {
      cycles++;
    }
    if (global.testingExposeCycleCount)
      global.dirtyCheckCycleCount = cycles;

    return cycles > 0;
  }

  function objectIsEmpty(object) {
    for (var prop in object)
      return false;
    return true;
  }

  function diffIsEmpty(diff) {
    return objectIsEmpty(diff.added) &&
           objectIsEmpty(diff.removed) &&
           objectIsEmpty(diff.changed);
  }

  function diffObjectFromOldObject(object, oldObject) {
    var added = {};
    var removed = {};
    var changed = {};

    for (var prop in oldObject) {
      var newValue = object[prop];

      if (newValue !== undefined && newValue === oldObject[prop])
        continue;

      if (!(prop in object)) {
        removed[prop] = undefined;
        continue;
      }

      if (newValue !== oldObject[prop])
        changed[prop] = newValue;
    }

    for (var prop in object) {
      if (prop in oldObject)
        continue;

      added[prop] = object[prop];
    }

    if (Array.isArray(object) && object.length !== oldObject.length)
      changed.length = object.length;

    return {
      added: added,
      removed: removed,
      changed: changed
    };
  }

  var eomTasks = [];
  function runEOMTasks() {
    if (!eomTasks.length)
      return false;

    for (var i = 0; i < eomTasks.length; i++) {
      eomTasks[i]();
    }
    eomTasks.length = 0;
    return true;
  }

  var runEOM = hasObserve ? (function(){
    var eomObj = { pingPong: true };
    var eomRunScheduled = false;

    Object.observe(eomObj, function() {
      runEOMTasks();
      eomRunScheduled = false;
    });

    return function(fn) {
      eomTasks.push(fn);
      if (!eomRunScheduled) {
        eomRunScheduled = true;
        eomObj.pingPong = !eomObj.pingPong;
      }
    };
  })() :
  (function() {
    return function(fn) {
      eomTasks.push(fn);
    };
  })();

  var observedObjectCache = [];

  function newObservedObject() {
    var observer;
    var object;
    var discardRecords = false;
    var first = true;

    function callback(records) {
      if (observer && observer.state_ === OPENED && !discardRecords)
        observer.check_(records);
    }

    return {
      open: function(obs) {
        if (observer)
          throw Error('ObservedObject in use');

        if (!first)
          Object.deliverChangeRecords(callback);

        observer = obs;
        first = false;
      },
      observe: function(obj, arrayObserve) {
        object = obj;
        if (arrayObserve)
          Array.observe(object, callback);
        else
          Object.observe(object, callback);
      },
      deliver: function(discard) {
        discardRecords = discard;
        Object.deliverChangeRecords(callback);
        discardRecords = false;
      },
      close: function() {
        observer = undefined;
        Object.unobserve(object, callback);
        observedObjectCache.push(this);
      }
    };
  }

  function getObservedObject(observer, object, arrayObserve) {
    var dir = observedObjectCache.pop() || newObservedObject();
    dir.open(observer);
    dir.observe(object, arrayObserve);
    return dir;
  }

  var emptyArray = [];
  var observedSetCache = [];

  function newObservedSet() {
    var observers = [];
    var observerCount = 0;
    var objects = [];
    var toRemove = emptyArray;
    var resetNeeded = false;
    var resetScheduled = false;

    function observe(obj) {
      if (!obj)
        return;

      var index = toRemove.indexOf(obj);
      if (index >= 0) {
        toRemove[index] = undefined;
        objects.push(obj);
      } else if (objects.indexOf(obj) < 0) {
        objects.push(obj);
        Object.observe(obj, callback);
      }

      observe(Object.getPrototypeOf(obj));
    }

    function reset() {
      var objs = toRemove === emptyArray ? [] : toRemove;
      toRemove = objects;
      objects = objs;

      var observer;
      for (var id in observers) {
        observer = observers[id];
        if (!observer || observer.state_ != OPENED)
          continue;

        observer.iterateObjects_(observe);
      }

      for (var i = 0; i < toRemove.length; i++) {
        var obj = toRemove[i];
        if (obj)
          Object.unobserve(obj, callback);
      }

      toRemove.length = 0;
    }

    function scheduledReset() {
      resetScheduled = false;
      if (!resetNeeded)
        return;

      reset();
    }

    function scheduleReset() {
      if (resetScheduled)
        return;

      resetNeeded = true;
      resetScheduled = true;
      runEOM(scheduledReset);
    }

    function callback() {
      reset();

      var observer;

      for (var id in observers) {
        observer = observers[id];
        if (!observer || observer.state_ != OPENED)
          continue;

        observer.check_();
      }
    }

    var record = {
      object: undefined,
      objects: objects,
      open: function(obs) {
        observers[obs.id_] = obs;
        observerCount++;
        obs.iterateObjects_(observe);
      },
      close: function(obs) {
        var anyLeft = false;

        observers[obs.id_] = undefined;
        observerCount--;

        if (observerCount) {
          scheduleReset();
          return;
        }
        resetNeeded = false;

        for (var i = 0; i < objects.length; i++) {
          Object.unobserve(objects[i], callback);
          Observer.unobservedCount++;
        }

        observers.length = 0;
        objects.length = 0;
        observedSetCache.push(this);
      },
      reset: scheduleReset
    };

    return record;
  }

  var lastObservedSet;

  function getObservedSet(observer, obj) {
    if (!lastObservedSet || lastObservedSet.object !== obj) {
      lastObservedSet = observedSetCache.pop() || newObservedSet();
      lastObservedSet.object = obj;
    }
    lastObservedSet.open(observer);
    return lastObservedSet;
  }

  var UNOPENED = 0;
  var OPENED = 1;
  var CLOSED = 2;
  var RESETTING = 3;

  var nextObserverId = 1;

  function Observer() {
    this.state_ = UNOPENED;
    this.callback_ = undefined;
    this.target_ = undefined; // TODO(rafaelw): Should be WeakRef
    this.directObserver_ = undefined;
    this.value_ = undefined;
    this.id_ = nextObserverId++;
  }

  Observer.prototype = {
    open: function(callback, target) {
      if (this.state_ != UNOPENED)
        throw Error('Observer has already been opened.');

      addToAll(this);
      this.callback_ = callback;
      this.target_ = target;
      this.state_ = OPENED;
      this.connect_();
      return this.value_;
    },

    close: function() {
      if (this.state_ != OPENED)
        return;

      removeFromAll(this);
      this.state_ = CLOSED;
      this.disconnect_();
      this.value_ = undefined;
      this.callback_ = undefined;
      this.target_ = undefined;
    },

    deliver: function() {
      if (this.state_ != OPENED)
        return;

      dirtyCheck(this);
    },

    report_: function(changes) {
      try {
        this.callback_.apply(this.target_, changes);
      } catch (ex) {
        Observer._errorThrownDuringCallback = true;
        console.error('Exception caught during observer callback: ' +
                       (ex.stack || ex));
      }
    },

    discardChanges: function() {
      this.check_(undefined, true);
      return this.value_;
    }
  }

  var collectObservers = !hasObserve;
  var allObservers;
  Observer._allObserversCount = 0;

  if (collectObservers) {
    allObservers = [];
  }

  function addToAll(observer) {
    Observer._allObserversCount++;
    if (!collectObservers)
      return;

    allObservers.push(observer);
  }

  function removeFromAll(observer) {
    Observer._allObserversCount--;
  }

  var runningMicrotaskCheckpoint = false;

  var hasDebugForceFullDelivery = hasObserve && (function() {
    try {
      eval('%RunMicrotasks()');
      return true;
    } catch (ex) {
      return false;
    }
  })();

  global.Platform = global.Platform || {};

  global.Platform.performMicrotaskCheckpoint = function() {
    if (runningMicrotaskCheckpoint)
      return;

    if (hasDebugForceFullDelivery) {
      eval('%RunMicrotasks()');
      return;
    }

    if (!collectObservers)
      return;

    runningMicrotaskCheckpoint = true;

    var cycles = 0;
    var anyChanged, toCheck;

    do {
      cycles++;
      toCheck = allObservers;
      allObservers = [];
      anyChanged = false;

      for (var i = 0; i < toCheck.length; i++) {
        var observer = toCheck[i];
        if (observer.state_ != OPENED)
          continue;

        if (observer.check_())
          anyChanged = true;

        allObservers.push(observer);
      }
      if (runEOMTasks())
        anyChanged = true;
    } while (cycles < MAX_DIRTY_CHECK_CYCLES && anyChanged);

    if (global.testingExposeCycleCount)
      global.dirtyCheckCycleCount = cycles;

    runningMicrotaskCheckpoint = false;
  };

  if (collectObservers) {
    global.Platform.clearObservers = function() {
      allObservers = [];
    };
  }

  function ObjectObserver(object) {
    Observer.call(this);
    this.value_ = object;
    this.oldObject_ = undefined;
  }

  ObjectObserver.prototype = createObject({
    __proto__: Observer.prototype,

    arrayObserve: false,

    connect_: function(callback, target) {
      if (hasObserve) {
        this.directObserver_ = getObservedObject(this, this.value_,
                                                 this.arrayObserve);
      } else {
        this.oldObject_ = this.copyObject(this.value_);
      }

    },

    copyObject: function(object) {
      var copy = Array.isArray(object) ? [] : {};
      for (var prop in object) {
        copy[prop] = object[prop];
      };
      if (Array.isArray(object))
        copy.length = object.length;
      return copy;
    },

    check_: function(changeRecords, skipChanges) {
      var diff;
      var oldValues;
      if (hasObserve) {
        if (!changeRecords)
          return false;

        oldValues = {};
        diff = diffObjectFromChangeRecords(this.value_, changeRecords,
                                           oldValues);
      } else {
        oldValues = this.oldObject_;
        diff = diffObjectFromOldObject(this.value_, this.oldObject_);
      }

      if (diffIsEmpty(diff))
        return false;

      if (!hasObserve)
        this.oldObject_ = this.copyObject(this.value_);

      this.report_([
        diff.added || {},
        diff.removed || {},
        diff.changed || {},
        function(property) {
          return oldValues[property];
        }
      ]);

      return true;
    },

    disconnect_: function() {
      if (hasObserve) {
        this.directObserver_.close();
        this.directObserver_ = undefined;
      } else {
        this.oldObject_ = undefined;
      }
    },

    deliver: function() {
      if (this.state_ != OPENED)
        return;

      if (hasObserve)
        this.directObserver_.deliver(false);
      else
        dirtyCheck(this);
    },

    discardChanges: function() {
      if (this.directObserver_)
        this.directObserver_.deliver(true);
      else
        this.oldObject_ = this.copyObject(this.value_);

      return this.value_;
    }
  });

  function ArrayObserver(array) {
    if (!Array.isArray(array))
      throw Error('Provided object is not an Array');
    ObjectObserver.call(this, array);
  }

  ArrayObserver.prototype = createObject({

    __proto__: ObjectObserver.prototype,

    arrayObserve: true,

    copyObject: function(arr) {
      return arr.slice();
    },

    check_: function(changeRecords) {
      var splices;
      if (hasObserve) {
        if (!changeRecords)
          return false;
        splices = projectArraySplices(this.value_, changeRecords);
      } else {
        splices = calcSplices(this.value_, 0, this.value_.length,
                              this.oldObject_, 0, this.oldObject_.length);
      }

      if (!splices || !splices.length)
        return false;

      if (!hasObserve)
        this.oldObject_ = this.copyObject(this.value_);

      this.report_([splices]);
      return true;
    }
  });

  ArrayObserver.applySplices = function(previous, current, splices) {
    splices.forEach(function(splice) {
      var spliceArgs = [splice.index, splice.removed.length];
      var addIndex = splice.index;
      while (addIndex < splice.index + splice.addedCount) {
        spliceArgs.push(current[addIndex]);
        addIndex++;
      }

      Array.prototype.splice.apply(previous, spliceArgs);
    });
  };

  function PathObserver(object, path) {
    Observer.call(this);

    this.object_ = object;
    this.path_ = path instanceof Path ? path : getPath(path);
    this.directObserver_ = undefined;
  }

  PathObserver.prototype = createObject({
    __proto__: Observer.prototype,

    connect_: function() {
      if (hasObserve)
        this.directObserver_ = getObservedSet(this, this.object_);

      this.check_(undefined, true);
    },

    disconnect_: function() {
      this.value_ = undefined;

      if (this.directObserver_) {
        this.directObserver_.close(this);
        this.directObserver_ = undefined;
      }
    },

    iterateObjects_: function(observe) {
      this.path_.iterateObjects(this.object_, observe);
    },

    check_: function(changeRecords, skipChanges) {
      var oldValue = this.value_;
      this.value_ = this.path_.getValueFrom(this.object_);
      if (skipChanges || areSameValue(this.value_, oldValue))
        return false;

      this.report_([this.value_, oldValue]);
      return true;
    },

    setValue: function(newValue) {
      if (this.path_)
        this.path_.setValueFrom(this.object_, newValue);
    }
  });

  function CompoundObserver() {
    Observer.call(this);

    this.value_ = [];
    this.directObserver_ = undefined;
    this.observed_ = [];
  }

  var observerSentinel = {};

  CompoundObserver.prototype = createObject({
    __proto__: Observer.prototype,

    connect_: function() {
      this.check_(undefined, true);

      if (!hasObserve)
        return;

      var object;
      var needsDirectObserver = false;
      for (var i = 0; i < this.observed_.length; i += 2) {
        object = this.observed_[i]
        if (object !== observerSentinel) {
          needsDirectObserver = true;
          break;
        }
      }

      if (this.directObserver_) {
        if (needsDirectObserver) {
          this.directObserver_.reset();
          return;
        }
        this.directObserver_.close();
        this.directObserver_ = undefined;
        return;
      }

      if (needsDirectObserver)
        this.directObserver_ = getObservedSet(this, object);
    },

    closeObservers_: function() {
      for (var i = 0; i < this.observed_.length; i += 2) {
        if (this.observed_[i] === observerSentinel)
          this.observed_[i + 1].close();
      }
      this.observed_.length = 0;
    },

    disconnect_: function() {
      this.value_ = undefined;

      if (this.directObserver_) {
        this.directObserver_.close(this);
        this.directObserver_ = undefined;
      }

      this.closeObservers_();
    },

    addPath: function(object, path) {
      if (this.state_ != UNOPENED && this.state_ != RESETTING)
        throw Error('Cannot add paths once started.');

      this.observed_.push(object, path instanceof Path ? path : getPath(path));
    },

    addObserver: function(observer) {
      if (this.state_ != UNOPENED && this.state_ != RESETTING)
        throw Error('Cannot add observers once started.');

      observer.open(this.deliver, this);
      this.observed_.push(observerSentinel, observer);
    },

    startReset: function() {
      if (this.state_ != OPENED)
        throw Error('Can only reset while open');

      this.state_ = RESETTING;
      this.closeObservers_();
    },

    finishReset: function() {
      if (this.state_ != RESETTING)
        throw Error('Can only finishReset after startReset');
      this.state_ = OPENED;
      this.connect_();

      return this.value_;
    },

    iterateObjects_: function(observe) {
      var object;
      for (var i = 0; i < this.observed_.length; i += 2) {
        object = this.observed_[i]
        if (object !== observerSentinel)
          this.observed_[i + 1].iterateObjects(object, observe)
      }
    },

    check_: function(changeRecords, skipChanges) {
      var oldValues;
      for (var i = 0; i < this.observed_.length; i += 2) {
        var pathOrObserver = this.observed_[i+1];
        var object = this.observed_[i];
        var value = object === observerSentinel ?
            pathOrObserver.discardChanges() :
            pathOrObserver.getValueFrom(object)

        if (skipChanges) {
          this.value_[i / 2] = value;
          continue;
        }

        if (areSameValue(value, this.value_[i / 2]))
          continue;

        oldValues = oldValues || [];
        oldValues[i / 2] = this.value_[i / 2];
        this.value_[i / 2] = value;
      }

      if (!oldValues)
        return false;

      // TODO(rafaelw): Having observed_ as the third callback arg here is
      // pretty lame API. Fix.
      this.report_([this.value_, oldValues, this.observed_]);
      return true;
    }
  });

  function identFn(value) { return value; }

  function ObserverTransform(observable, getValueFn, setValueFn,
                             dontPassThroughSet) {
    this.callback_ = undefined;
    this.target_ = undefined;
    this.value_ = undefined;
    this.observable_ = observable;
    this.getValueFn_ = getValueFn || identFn;
    this.setValueFn_ = setValueFn || identFn;
    // TODO(rafaelw): This is a temporary hack. PolymerExpressions needs this
    // at the moment because of a bug in it's dependency tracking.
    this.dontPassThroughSet_ = dontPassThroughSet;
  }

  ObserverTransform.prototype = {
    open: function(callback, target) {
      this.callback_ = callback;
      this.target_ = target;
      this.value_ =
          this.getValueFn_(this.observable_.open(this.observedCallback_, this));
      return this.value_;
    },

    observedCallback_: function(value) {
      value = this.getValueFn_(value);
      if (areSameValue(value, this.value_))
        return;
      var oldValue = this.value_;
      this.value_ = value;
      this.callback_.call(this.target_, this.value_, oldValue);
    },

    discardChanges: function() {
      this.value_ = this.getValueFn_(this.observable_.discardChanges());
      return this.value_;
    },

    deliver: function() {
      return this.observable_.deliver();
    },

    setValue: function(value) {
      value = this.setValueFn_(value);
      if (!this.dontPassThroughSet_ && this.observable_.setValue)
        return this.observable_.setValue(value);
    },

    close: function() {
      if (this.observable_)
        this.observable_.close();
      this.callback_ = undefined;
      this.target_ = undefined;
      this.observable_ = undefined;
      this.value_ = undefined;
      this.getValueFn_ = undefined;
      this.setValueFn_ = undefined;
    }
  }

  var expectedRecordTypes = {
    add: true,
    update: true,
    delete: true
  };

  function notifyFunction(object, name) {
    if (typeof Object.observe !== 'function')
      return;

    var notifier = Object.getNotifier(object);
    return function(type, oldValue) {
      var changeRecord = {
        object: object,
        type: type,
        name: name
      };
      if (arguments.length === 2)
        changeRecord.oldValue = oldValue;
      notifier.notify(changeRecord);
    }
  }

  Observer.defineComputedProperty = function(target, name, observable) {
    var notify = notifyFunction(target, name);
    var value = observable.open(function(newValue, oldValue) {
      value = newValue;
      if (notify)
        notify('update', oldValue);
    });

    Object.defineProperty(target, name, {
      get: function() {
        observable.deliver();
        return value;
      },
      set: function(newValue) {
        observable.setValue(newValue);
        return newValue;
      },
      configurable: true
    });

    return {
      close: function() {
        observable.close();
        Object.defineProperty(target, name, {
          value: value,
          writable: true,
          configurable: true
        });
      }
    };
  }

  function diffObjectFromChangeRecords(object, changeRecords, oldValues) {
    var added = {};
    var removed = {};

    for (var i = 0; i < changeRecords.length; i++) {
      var record = changeRecords[i];
      if (!expectedRecordTypes[record.type]) {
        console.error('Unknown changeRecord type: ' + record.type);
        console.error(record);
        continue;
      }

      if (!(record.name in oldValues))
        oldValues[record.name] = record.oldValue;

      if (record.type == 'update')
        continue;

      if (record.type == 'add') {
        if (record.name in removed)
          delete removed[record.name];
        else
          added[record.name] = true;

        continue;
      }

      // type = 'delete'
      if (record.name in added) {
        delete added[record.name];
        delete oldValues[record.name];
      } else {
        removed[record.name] = true;
      }
    }

    for (var prop in added)
      added[prop] = object[prop];

    for (var prop in removed)
      removed[prop] = undefined;

    var changed = {};
    for (var prop in oldValues) {
      if (prop in added || prop in removed)
        continue;

      var newValue = object[prop];
      if (oldValues[prop] !== newValue)
        changed[prop] = newValue;
    }

    return {
      added: added,
      removed: removed,
      changed: changed
    };
  }

  function newSplice(index, removed, addedCount) {
    return {
      index: index,
      removed: removed,
      addedCount: addedCount
    };
  }

  var EDIT_LEAVE = 0;
  var EDIT_UPDATE = 1;
  var EDIT_ADD = 2;
  var EDIT_DELETE = 3;

  function ArraySplice() {}

  ArraySplice.prototype = {

    // Note: This function is *based* on the computation of the Levenshtein
    // "edit" distance. The one change is that "updates" are treated as two
    // edits - not one. With Array splices, an update is really a delete
    // followed by an add. By retaining this, we optimize for "keeping" the
    // maximum array items in the original array. For example:
    //
    //   'xxxx123' -> '123yyyy'
    //
    // With 1-edit updates, the shortest path would be just to update all seven
    // characters. With 2-edit updates, we delete 4, leave 3, and add 4. This
    // leaves the substring '123' intact.
    calcEditDistances: function(current, currentStart, currentEnd,
                                old, oldStart, oldEnd) {
      // "Deletion" columns
      var rowCount = oldEnd - oldStart + 1;
      var columnCount = currentEnd - currentStart + 1;
      var distances = new Array(rowCount);

      // "Addition" rows. Initialize null column.
      for (var i = 0; i < rowCount; i++) {
        distances[i] = new Array(columnCount);
        distances[i][0] = i;
      }

      // Initialize null row
      for (var j = 0; j < columnCount; j++)
        distances[0][j] = j;

      for (var i = 1; i < rowCount; i++) {
        for (var j = 1; j < columnCount; j++) {
          if (this.equals(current[currentStart + j - 1], old[oldStart + i - 1]))
            distances[i][j] = distances[i - 1][j - 1];
          else {
            var north = distances[i - 1][j] + 1;
            var west = distances[i][j - 1] + 1;
            distances[i][j] = north < west ? north : west;
          }
        }
      }

      return distances;
    },

    // This starts at the final weight, and walks "backward" by finding
    // the minimum previous weight recursively until the origin of the weight
    // matrix.
    spliceOperationsFromEditDistances: function(distances) {
      var i = distances.length - 1;
      var j = distances[0].length - 1;
      var current = distances[i][j];
      var edits = [];
      while (i > 0 || j > 0) {
        if (i == 0) {
          edits.push(EDIT_ADD);
          j--;
          continue;
        }
        if (j == 0) {
          edits.push(EDIT_DELETE);
          i--;
          continue;
        }
        var northWest = distances[i - 1][j - 1];
        var west = distances[i - 1][j];
        var north = distances[i][j - 1];

        var min;
        if (west < north)
          min = west < northWest ? west : northWest;
        else
          min = north < northWest ? north : northWest;

        if (min == northWest) {
          if (northWest == current) {
            edits.push(EDIT_LEAVE);
          } else {
            edits.push(EDIT_UPDATE);
            current = northWest;
          }
          i--;
          j--;
        } else if (min == west) {
          edits.push(EDIT_DELETE);
          i--;
          current = west;
        } else {
          edits.push(EDIT_ADD);
          j--;
          current = north;
        }
      }

      edits.reverse();
      return edits;
    },

    /**
     * Splice Projection functions:
     *
     * A splice map is a representation of how a previous array of items
     * was transformed into a new array of items. Conceptually it is a list of
     * tuples of
     *
     *   <index, removed, addedCount>
     *
     * which are kept in ascending index order of. The tuple represents that at
     * the |index|, |removed| sequence of items were removed, and counting forward
     * from |index|, |addedCount| items were added.
     */

    /**
     * Lacking individual splice mutation information, the minimal set of
     * splices can be synthesized given the previous state and final state of an
     * array. The basic approach is to calculate the edit distance matrix and
     * choose the shortest path through it.
     *
     * Complexity: O(l * p)
     *   l: The length of the current array
     *   p: The length of the old array
     */
    calcSplices: function(current, currentStart, currentEnd,
                          old, oldStart, oldEnd) {
      var prefixCount = 0;
      var suffixCount = 0;

      var minLength = Math.min(currentEnd - currentStart, oldEnd - oldStart);
      if (currentStart == 0 && oldStart == 0)
        prefixCount = this.sharedPrefix(current, old, minLength);

      if (currentEnd == current.length && oldEnd == old.length)
        suffixCount = this.sharedSuffix(current, old, minLength - prefixCount);

      currentStart += prefixCount;
      oldStart += prefixCount;
      currentEnd -= suffixCount;
      oldEnd -= suffixCount;

      if (currentEnd - currentStart == 0 && oldEnd - oldStart == 0)
        return [];

      if (currentStart == currentEnd) {
        var splice = newSplice(currentStart, [], 0);
        while (oldStart < oldEnd)
          splice.removed.push(old[oldStart++]);

        return [ splice ];
      } else if (oldStart == oldEnd)
        return [ newSplice(currentStart, [], currentEnd - currentStart) ];

      var ops = this.spliceOperationsFromEditDistances(
          this.calcEditDistances(current, currentStart, currentEnd,
                                 old, oldStart, oldEnd));

      var splice = undefined;
      var splices = [];
      var index = currentStart;
      var oldIndex = oldStart;
      for (var i = 0; i < ops.length; i++) {
        switch(ops[i]) {
          case EDIT_LEAVE:
            if (splice) {
              splices.push(splice);
              splice = undefined;
            }

            index++;
            oldIndex++;
            break;
          case EDIT_UPDATE:
            if (!splice)
              splice = newSplice(index, [], 0);

            splice.addedCount++;
            index++;

            splice.removed.push(old[oldIndex]);
            oldIndex++;
            break;
          case EDIT_ADD:
            if (!splice)
              splice = newSplice(index, [], 0);

            splice.addedCount++;
            index++;
            break;
          case EDIT_DELETE:
            if (!splice)
              splice = newSplice(index, [], 0);

            splice.removed.push(old[oldIndex]);
            oldIndex++;
            break;
        }
      }

      if (splice) {
        splices.push(splice);
      }
      return splices;
    },

    sharedPrefix: function(current, old, searchLength) {
      for (var i = 0; i < searchLength; i++)
        if (!this.equals(current[i], old[i]))
          return i;
      return searchLength;
    },

    sharedSuffix: function(current, old, searchLength) {
      var index1 = current.length;
      var index2 = old.length;
      var count = 0;
      while (count < searchLength && this.equals(current[--index1], old[--index2]))
        count++;

      return count;
    },

    calculateSplices: function(current, previous) {
      return this.calcSplices(current, 0, current.length, previous, 0,
                              previous.length);
    },

    equals: function(currentValue, previousValue) {
      return currentValue === previousValue;
    }
  };

  var arraySplice = new ArraySplice();

  function calcSplices(current, currentStart, currentEnd,
                       old, oldStart, oldEnd) {
    return arraySplice.calcSplices(current, currentStart, currentEnd,
                                   old, oldStart, oldEnd);
  }

  function intersect(start1, end1, start2, end2) {
    // Disjoint
    if (end1 < start2 || end2 < start1)
      return -1;

    // Adjacent
    if (end1 == start2 || end2 == start1)
      return 0;

    // Non-zero intersect, span1 first
    if (start1 < start2) {
      if (end1 < end2)
        return end1 - start2; // Overlap
      else
        return end2 - start2; // Contained
    } else {
      // Non-zero intersect, span2 first
      if (end2 < end1)
        return end2 - start1; // Overlap
      else
        return end1 - start1; // Contained
    }
  }

  function mergeSplice(splices, index, removed, addedCount) {

    var splice = newSplice(index, removed, addedCount);

    var inserted = false;
    var insertionOffset = 0;

    for (var i = 0; i < splices.length; i++) {
      var current = splices[i];
      current.index += insertionOffset;

      if (inserted)
        continue;

      var intersectCount = intersect(splice.index,
                                     splice.index + splice.removed.length,
                                     current.index,
                                     current.index + current.addedCount);

      if (intersectCount >= 0) {
        // Merge the two splices

        splices.splice(i, 1);
        i--;

        insertionOffset -= current.addedCount - current.removed.length;

        splice.addedCount += current.addedCount - intersectCount;
        var deleteCount = splice.removed.length +
                          current.removed.length - intersectCount;

        if (!splice.addedCount && !deleteCount) {
          // merged splice is a noop. discard.
          inserted = true;
        } else {
          var removed = current.removed;

          if (splice.index < current.index) {
            // some prefix of splice.removed is prepended to current.removed.
            var prepend = splice.removed.slice(0, current.index - splice.index);
            Array.prototype.push.apply(prepend, removed);
            removed = prepend;
          }

          if (splice.index + splice.removed.length > current.index + current.addedCount) {
            // some suffix of splice.removed is appended to current.removed.
            var append = splice.removed.slice(current.index + current.addedCount - splice.index);
            Array.prototype.push.apply(removed, append);
          }

          splice.removed = removed;
          if (current.index < splice.index) {
            splice.index = current.index;
          }
        }
      } else if (splice.index < current.index) {
        // Insert splice here.

        inserted = true;

        splices.splice(i, 0, splice);
        i++;

        var offset = splice.addedCount - splice.removed.length
        current.index += offset;
        insertionOffset += offset;
      }
    }

    if (!inserted)
      splices.push(splice);
  }

  function createInitialSplices(array, changeRecords) {
    var splices = [];

    for (var i = 0; i < changeRecords.length; i++) {
      var record = changeRecords[i];
      switch(record.type) {
        case 'splice':
          mergeSplice(splices, record.index, record.removed.slice(), record.addedCount);
          break;
        case 'add':
        case 'update':
        case 'delete':
          if (!isIndex(record.name))
            continue;
          var index = toNumber(record.name);
          if (index < 0)
            continue;
          mergeSplice(splices, index, [record.oldValue], 1);
          break;
        default:
          console.error('Unexpected record type: ' + JSON.stringify(record));
          break;
      }
    }

    return splices;
  }

  function projectArraySplices(array, changeRecords) {
    var splices = [];

    createInitialSplices(array, changeRecords).forEach(function(splice) {
      if (splice.addedCount == 1 && splice.removed.length == 1) {
        if (splice.removed[0] !== array[splice.index])
          splices.push(splice);

        return
      };

      splices = splices.concat(calcSplices(array, splice.index, splice.index + splice.addedCount,
                                           splice.removed, 0, splice.removed.length));
    });

    return splices;
  }

  global.Observer = Observer;
  global.Observer.runEOM_ = runEOM;
  global.Observer.hasObjectObserve = hasObserve;
  global.ArrayObserver = ArrayObserver;
  global.ArrayObserver.calculateSplices = function(current, previous) {
    return arraySplice.calculateSplices(current, previous);
  };

  global.ArraySplice = ArraySplice;
  global.ObjectObserver = ObjectObserver;
  global.PathObserver = PathObserver;
  global.CompoundObserver = CompoundObserver;
  global.Path = Path;
  global.ObserverTransform = ObserverTransform;
})(typeof global !== 'undefined' && global && typeof module !== 'undefined' && module ? global : this || window);

// prepoulate window.Platform.flags for default controls
window.Platform = window.Platform || {};
// prepopulate window.logFlags if necessary
window.logFlags = window.logFlags || {};
// process flags
(function(scope){
  // import
  var flags = scope.flags || {};
  // populate flags from location
  location.search.slice(1).split('&').forEach(function(o) {
    o = o.split('=');
    o[0] && (flags[o[0]] = o[1] || true);
  });
  var entryPoint = document.currentScript ||
      document.querySelector('script[src*="platform.js"]');
  if (entryPoint) {
    var a = entryPoint.attributes;
    for (var i = 0, n; i < a.length; i++) {
      n = a[i];
      if (n.name !== 'src') {
        flags[n.name] = n.value || true;
      }
    }
  }
  if (flags.log) {
    flags.log.split(',').forEach(function(f) {
      window.logFlags[f] = true;
    });
  }
  // If any of these flags match 'native', then force native ShadowDOM; any
  // other truthy value, or failure to detect native
  // ShadowDOM, results in polyfill
  flags.shadow = flags.shadow || flags.shadowdom || flags.polyfill;
  if (flags.shadow === 'native') {
    flags.shadow = false;
  } else {
    flags.shadow = flags.shadow || !HTMLElement.prototype.createShadowRoot;
  }

  if (flags.shadow && document.querySelectorAll('script').length > 1) {
    console.warn('platform.js is not the first script on the page. ' +
        'See http://www.polymer-project.org/docs/start/platform.html#setup ' +
        'for details.');
  }

  // CustomElements polyfill flag
  if (flags.register) {
    window.CustomElements = window.CustomElements || {flags: {}};
    window.CustomElements.flags.register = flags.register;
  }

  if (flags.imports) {
    window.HTMLImports = window.HTMLImports || {flags: {}};
    window.HTMLImports.flags.imports = flags.imports;
  }

  // export
  scope.flags = flags;
})(Platform);

// select ShadowDOM impl
if (Platform.flags.shadow) {

// Copyright 2012 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

window.ShadowDOMPolyfill = {};

(function(scope) {
  'use strict';

  var constructorTable = new WeakMap();
  var nativePrototypeTable = new WeakMap();
  var wrappers = Object.create(null);

  // Don't test for eval if document has CSP securityPolicy object and we can
  // see that eval is not supported. This avoids an error message in console
  // even when the exception is caught
  var hasEval = !('securityPolicy' in document) ||
      document.securityPolicy.allowsEval;
  if (hasEval) {
    try {
      var f = new Function('', 'return true;');
      hasEval = f();
    } catch (ex) {
      hasEval = false;
    }
  }

  function assert(b) {
    if (!b)
      throw new Error('Assertion failed');
  };

  var defineProperty = Object.defineProperty;
  var getOwnPropertyNames = Object.getOwnPropertyNames;
  var getOwnPropertyDescriptor = Object.getOwnPropertyDescriptor;

  function mixin(to, from) {
    getOwnPropertyNames(from).forEach(function(name) {
      defineProperty(to, name, getOwnPropertyDescriptor(from, name));
    });
    return to;
  };

  function mixinStatics(to, from) {
    getOwnPropertyNames(from).forEach(function(name) {
      switch (name) {
        case 'arguments':
        case 'caller':
        case 'length':
        case 'name':
        case 'prototype':
        case 'toString':
          return;
      }
      defineProperty(to, name, getOwnPropertyDescriptor(from, name));
    });
    return to;
  };

  function oneOf(object, propertyNames) {
    for (var i = 0; i < propertyNames.length; i++) {
      if (propertyNames[i] in object)
        return propertyNames[i];
    }
  }

  // Mozilla's old DOM bindings are bretty busted:
  // https://bugzilla.mozilla.org/show_bug.cgi?id=855844
  // Make sure they are create before we start modifying things.
  getOwnPropertyNames(window);

  function getWrapperConstructor(node) {
    var nativePrototype = node.__proto__ || Object.getPrototypeOf(node);
    var wrapperConstructor = constructorTable.get(nativePrototype);
    if (wrapperConstructor)
      return wrapperConstructor;

    var parentWrapperConstructor = getWrapperConstructor(nativePrototype);

    var GeneratedWrapper = createWrapperConstructor(parentWrapperConstructor);
    registerInternal(nativePrototype, GeneratedWrapper, node);

    return GeneratedWrapper;
  }

  function addForwardingProperties(nativePrototype, wrapperPrototype) {
    installProperty(nativePrototype, wrapperPrototype, true);
  }

  function registerInstanceProperties(wrapperPrototype, instanceObject) {
    installProperty(instanceObject, wrapperPrototype, false);
  }

  var isFirefox = /Firefox/.test(navigator.userAgent);

  // This is used as a fallback when getting the descriptor fails in
  // installProperty.
  var dummyDescriptor = {
    get: function() {},
    set: function(v) {},
    configurable: true,
    enumerable: true
  };

  function isEventHandlerName(name) {
    return /^on[a-z]+$/.test(name);
  }

  function isIdentifierName(name) {
    return /^\w[a-zA-Z_0-9]*$/.test(name);
  }

  function getGetter(name) {
    return hasEval && isIdentifierName(name) ?
        new Function('return this.impl.' + name) :
        function() { return this.impl[name]; };
  }

  function getSetter(name) {
    return hasEval && isIdentifierName(name) ?
        new Function('v', 'this.impl.' + name + ' = v') :
        function(v) { this.impl[name] = v; };
  }

  function getMethod(name) {
    return hasEval && isIdentifierName(name) ?
        new Function('return this.impl.' + name +
                     '.apply(this.impl, arguments)') :
        function() { return this.impl[name].apply(this.impl, arguments); };
  }

  function getDescriptor(source, name) {
    try {
      return Object.getOwnPropertyDescriptor(source, name);
    } catch (ex) {
      // JSC and V8 both use data properties instead of accessors which can
      // cause getting the property desciptor to throw an exception.
      // https://bugs.webkit.org/show_bug.cgi?id=49739
      return dummyDescriptor;
    }
  }

  function installProperty(source, target, allowMethod, opt_blacklist) {
    var names = getOwnPropertyNames(source);
    for (var i = 0; i < names.length; i++) {
      var name = names[i];
      if (name === 'polymerBlackList_')
        continue;

      if (name in target)
        continue;

      if (source.polymerBlackList_ && source.polymerBlackList_[name])
        continue;

      if (isFirefox) {
        // Tickle Firefox's old bindings.
        source.__lookupGetter__(name);
      }
      var descriptor = getDescriptor(source, name);
      var getter, setter;
      if (allowMethod && typeof descriptor.value === 'function') {
        target[name] = getMethod(name);
        continue;
      }

      var isEvent = isEventHandlerName(name);
      if (isEvent)
        getter = scope.getEventHandlerGetter(name);
      else
        getter = getGetter(name);

      if (descriptor.writable || descriptor.set) {
        if (isEvent)
          setter = scope.getEventHandlerSetter(name);
        else
          setter = getSetter(name);
      }

      defineProperty(target, name, {
        get: getter,
        set: setter,
        configurable: descriptor.configurable,
        enumerable: descriptor.enumerable
      });
    }
  }

  /**
   * @param {Function} nativeConstructor
   * @param {Function} wrapperConstructor
   * @param {Object=} opt_instance If present, this is used to extract
   *     properties from an instance object.
   */
  function register(nativeConstructor, wrapperConstructor, opt_instance) {
    var nativePrototype = nativeConstructor.prototype;
    registerInternal(nativePrototype, wrapperConstructor, opt_instance);
    mixinStatics(wrapperConstructor, nativeConstructor);
  }

  function registerInternal(nativePrototype, wrapperConstructor, opt_instance) {
    var wrapperPrototype = wrapperConstructor.prototype;
    assert(constructorTable.get(nativePrototype) === undefined);

    constructorTable.set(nativePrototype, wrapperConstructor);
    nativePrototypeTable.set(wrapperPrototype, nativePrototype);

    addForwardingProperties(nativePrototype, wrapperPrototype);
    if (opt_instance)
      registerInstanceProperties(wrapperPrototype, opt_instance);
    defineProperty(wrapperPrototype, 'constructor', {
      value: wrapperConstructor,
      configurable: true,
      enumerable: false,
      writable: true
    });
    // Set it again. Some VMs optimizes objects that are used as prototypes.
    wrapperConstructor.prototype = wrapperPrototype;
  }

  function isWrapperFor(wrapperConstructor, nativeConstructor) {
    return constructorTable.get(nativeConstructor.prototype) ===
        wrapperConstructor;
  }

  /**
   * Creates a generic wrapper constructor based on |object| and its
   * constructor.
   * @param {Node} object
   * @return {Function} The generated constructor.
   */
  function registerObject(object) {
    var nativePrototype = Object.getPrototypeOf(object);

    var superWrapperConstructor = getWrapperConstructor(nativePrototype);
    var GeneratedWrapper = createWrapperConstructor(superWrapperConstructor);
    registerInternal(nativePrototype, GeneratedWrapper, object);

    return GeneratedWrapper;
  }

  function createWrapperConstructor(superWrapperConstructor) {
    function GeneratedWrapper(node) {
      superWrapperConstructor.call(this, node);
    }
    var p = Object.create(superWrapperConstructor.prototype);
    p.constructor = GeneratedWrapper;
    GeneratedWrapper.prototype = p;

    return GeneratedWrapper;
  }

  var OriginalDOMImplementation = window.DOMImplementation;
  var OriginalEventTarget = window.EventTarget;
  var OriginalEvent = window.Event;
  var OriginalNode = window.Node;
  var OriginalWindow = window.Window;
  var OriginalRange = window.Range;
  var OriginalCanvasRenderingContext2D = window.CanvasRenderingContext2D;
  var OriginalWebGLRenderingContext = window.WebGLRenderingContext;
  var OriginalSVGElementInstance = window.SVGElementInstance;

  function isWrapper(object) {
    return object instanceof wrappers.EventTarget ||
           object instanceof wrappers.Event ||
           object instanceof wrappers.Range ||
           object instanceof wrappers.DOMImplementation ||
           object instanceof wrappers.CanvasRenderingContext2D ||
           wrappers.WebGLRenderingContext &&
               object instanceof wrappers.WebGLRenderingContext;
  }

  function isNative(object) {
    return OriginalEventTarget && object instanceof OriginalEventTarget ||
           object instanceof OriginalNode ||
           object instanceof OriginalEvent ||
           object instanceof OriginalWindow ||
           object instanceof OriginalRange ||
           object instanceof OriginalDOMImplementation ||
           object instanceof OriginalCanvasRenderingContext2D ||
           OriginalWebGLRenderingContext &&
               object instanceof OriginalWebGLRenderingContext ||
           OriginalSVGElementInstance &&
               object instanceof OriginalSVGElementInstance;
  }

  /**
   * Wraps a node in a WrapperNode. If there already exists a wrapper for the
   * |node| that wrapper is returned instead.
   * @param {Node} node
   * @return {WrapperNode}
   */
  function wrap(impl) {
    if (impl === null)
      return null;

    assert(isNative(impl));
    return impl.polymerWrapper_ ||
        (impl.polymerWrapper_ = new (getWrapperConstructor(impl))(impl));
  }

  /**
   * Unwraps a wrapper and returns the node it is wrapping.
   * @param {WrapperNode} wrapper
   * @return {Node}
   */
  function unwrap(wrapper) {
    if (wrapper === null)
      return null;
    assert(isWrapper(wrapper));
    return wrapper.impl;
  }

  /**
   * Unwraps object if it is a wrapper.
   * @param {Object} object
   * @return {Object} The native implementation object.
   */
  function unwrapIfNeeded(object) {
    return object && isWrapper(object) ? unwrap(object) : object;
  }

  /**
   * Wraps object if it is not a wrapper.
   * @param {Object} object
   * @return {Object} The wrapper for object.
   */
  function wrapIfNeeded(object) {
    return object && !isWrapper(object) ? wrap(object) : object;
  }

  /**
   * Overrides the current wrapper (if any) for node.
   * @param {Node} node
   * @param {WrapperNode=} wrapper If left out the wrapper will be created as
   *     needed next time someone wraps the node.
   */
  function rewrap(node, wrapper) {
    if (wrapper === null)
      return;
    assert(isNative(node));
    assert(wrapper === undefined || isWrapper(wrapper));
    node.polymerWrapper_ = wrapper;
  }

  function defineGetter(constructor, name, getter) {
    defineProperty(constructor.prototype, name, {
      get: getter,
      configurable: true,
      enumerable: true
    });
  }

  function defineWrapGetter(constructor, name) {
    defineGetter(constructor, name, function() {
      return wrap(this.impl[name]);
    });
  }

  /**
   * Forwards existing methods on the native object to the wrapper methods.
   * This does not wrap any of the arguments or the return value since the
   * wrapper implementation already takes care of that.
   * @param {Array.<Function>} constructors
   * @parem {Array.<string>} names
   */
  function forwardMethodsToWrapper(constructors, names) {
    constructors.forEach(function(constructor) {
      names.forEach(function(name) {
        constructor.prototype[name] = function() {
          var w = wrapIfNeeded(this);
          return w[name].apply(w, arguments);
        };
      });
    });
  }

  scope.assert = assert;
  scope.constructorTable = constructorTable;
  scope.defineGetter = defineGetter;
  scope.defineWrapGetter = defineWrapGetter;
  scope.forwardMethodsToWrapper = forwardMethodsToWrapper;
  scope.isWrapper = isWrapper;
  scope.isWrapperFor = isWrapperFor;
  scope.mixin = mixin;
  scope.nativePrototypeTable = nativePrototypeTable;
  scope.oneOf = oneOf;
  scope.registerObject = registerObject;
  scope.registerWrapper = register;
  scope.rewrap = rewrap;
  scope.unwrap = unwrap;
  scope.unwrapIfNeeded = unwrapIfNeeded;
  scope.wrap = wrap;
  scope.wrapIfNeeded = wrapIfNeeded;
  scope.wrappers = wrappers;

})(window.ShadowDOMPolyfill);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is goverened by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(context) {
  'use strict';

  var OriginalMutationObserver = window.MutationObserver;
  var callbacks = [];
  var pending = false;
  var timerFunc;

  function handle() {
    pending = false;
    var copies = callbacks.slice(0);
    callbacks = [];
    for (var i = 0; i < copies.length; i++) {
      (0, copies[i])();
    }
  }

  if (OriginalMutationObserver) {
    var counter = 1;
    var observer = new OriginalMutationObserver(handle);
    var textNode = document.createTextNode(counter);
    observer.observe(textNode, {characterData: true});

    timerFunc = function() {
      counter = (counter + 1) % 2;
      textNode.data = counter;
    };

  } else {
    timerFunc = window.setImmediate || window.setTimeout;
  }

  function setEndOfMicrotask(func) {
    callbacks.push(func);
    if (pending)
      return;
    pending = true;
    timerFunc(handle, 0);
  }

  context.setEndOfMicrotask = setEndOfMicrotask;

})(window.ShadowDOMPolyfill);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is goverened by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {
  'use strict';

  var setEndOfMicrotask = scope.setEndOfMicrotask
  var wrapIfNeeded = scope.wrapIfNeeded
  var wrappers = scope.wrappers;

  var registrationsTable = new WeakMap();
  var globalMutationObservers = [];
  var isScheduled = false;

  function scheduleCallback(observer) {
    if (isScheduled)
      return;
    setEndOfMicrotask(notifyObservers);
    isScheduled = true;
  }

  // http://dom.spec.whatwg.org/#mutation-observers
  function notifyObservers() {
    isScheduled = false;

    do {
      var notifyList = globalMutationObservers.slice();
      var anyNonEmpty = false;
      for (var i = 0; i < notifyList.length; i++) {
        var mo = notifyList[i];
        var queue = mo.takeRecords();
        removeTransientObserversFor(mo);
        if (queue.length) {
          mo.callback_(queue, mo);
          anyNonEmpty = true;
        }
      }
    } while (anyNonEmpty);
  }

  /**
   * @param {string} type
   * @param {Node} target
   * @constructor
   */
  function MutationRecord(type, target) {
    this.type = type;
    this.target = target;
    this.addedNodes = new wrappers.NodeList();
    this.removedNodes = new wrappers.NodeList();
    this.previousSibling = null;
    this.nextSibling = null;
    this.attributeName = null;
    this.attributeNamespace = null;
    this.oldValue = null;
  }

  /**
   * Registers transient observers to ancestor and its ancesors for the node
   * which was removed.
   * @param {!Node} ancestor
   * @param {!Node} node
   */
  function registerTransientObservers(ancestor, node) {
    for (; ancestor; ancestor = ancestor.parentNode) {
      var registrations = registrationsTable.get(ancestor);
      if (!registrations)
        continue;
      for (var i = 0; i < registrations.length; i++) {
        var registration = registrations[i];
        if (registration.options.subtree)
          registration.addTransientObserver(node);
      }
    }
  }

  function removeTransientObserversFor(observer) {
    for (var i = 0; i < observer.nodes_.length; i++) {
      var node = observer.nodes_[i];
      var registrations = registrationsTable.get(node);
      if (!registrations)
        return;
      for (var j = 0; j < registrations.length; j++) {
        var registration = registrations[j];
        if (registration.observer === observer)
          registration.removeTransientObservers();
      }
    }
  }

  // http://dom.spec.whatwg.org/#queue-a-mutation-record
  function enqueueMutation(target, type, data) {
    // 1.
    var interestedObservers = Object.create(null);
    var associatedStrings = Object.create(null);

    // 2.
    for (var node = target; node; node = node.parentNode) {
      // 3.
      var registrations = registrationsTable.get(node);
      if (!registrations)
        continue;
      for (var j = 0; j < registrations.length; j++) {
        var registration = registrations[j];
        var options = registration.options;
        // 1.
        if (node !== target && !options.subtree)
          continue;

        // 2.
        if (type === 'attributes' && !options.attributes)
          continue;

        // 3. If type is "attributes", options's attributeFilter is present, and
        // either options's attributeFilter does not contain name or namespace
        // is non-null, continue.
        if (type === 'attributes' && options.attributeFilter &&
            (data.namespace !== null ||
             options.attributeFilter.indexOf(data.name) === -1)) {
          continue;
        }

        // 4.
        if (type === 'characterData' && !options.characterData)
          continue;

        // 5.
        if (type === 'childList' && !options.childList)
          continue;

        // 6.
        var observer = registration.observer;
        interestedObservers[observer.uid_] = observer;

        // 7. If either type is "attributes" and options's attributeOldValue is
        // true, or type is "characterData" and options's characterDataOldValue
        // is true, set the paired string of registered observer's observer in
        // interested observers to oldValue.
        if (type === 'attributes' && options.attributeOldValue ||
            type === 'characterData' && options.characterDataOldValue) {
          associatedStrings[observer.uid_] = data.oldValue;
        }
      }
    }

    var anyRecordsEnqueued = false;

    // 4.
    for (var uid in interestedObservers) {
      var observer = interestedObservers[uid];
      var record = new MutationRecord(type, target);

      // 2.
      if ('name' in data && 'namespace' in data) {
        record.attributeName = data.name;
        record.attributeNamespace = data.namespace;
      }

      // 3.
      if (data.addedNodes)
        record.addedNodes = data.addedNodes;

      // 4.
      if (data.removedNodes)
        record.removedNodes = data.removedNodes;

      // 5.
      if (data.previousSibling)
        record.previousSibling = data.previousSibling;

      // 6.
      if (data.nextSibling)
        record.nextSibling = data.nextSibling;

      // 7.
      if (associatedStrings[uid] !== undefined)
        record.oldValue = associatedStrings[uid];

      // 8.
      observer.records_.push(record);

      anyRecordsEnqueued = true;
    }

    if (anyRecordsEnqueued)
      scheduleCallback();
  }

  var slice = Array.prototype.slice;

  /**
   * @param {!Object} options
   * @constructor
   */
  function MutationObserverOptions(options) {
    this.childList = !!options.childList;
    this.subtree = !!options.subtree;

    // 1. If either options' attributeOldValue or attributeFilter is present
    // and options' attributes is omitted, set options' attributes to true.
    if (!('attributes' in options) &&
        ('attributeOldValue' in options || 'attributeFilter' in options)) {
      this.attributes = true;
    } else {
      this.attributes = !!options.attributes;
    }

    // 2. If options' characterDataOldValue is present and options'
    // characterData is omitted, set options' characterData to true.
    if ('characterDataOldValue' in options && !('characterData' in options))
      this.characterData = true;
    else
      this.characterData = !!options.characterData;

    // 3. & 4.
    if (!this.attributes &&
        (options.attributeOldValue || 'attributeFilter' in options) ||
        // 5.
        !this.characterData && options.characterDataOldValue) {
      throw new TypeError();
    }

    this.characterData = !!options.characterData;
    this.attributeOldValue = !!options.attributeOldValue;
    this.characterDataOldValue = !!options.characterDataOldValue;
    if ('attributeFilter' in options) {
      if (options.attributeFilter == null ||
          typeof options.attributeFilter !== 'object') {
        throw new TypeError();
      }
      this.attributeFilter = slice.call(options.attributeFilter);
    } else {
      this.attributeFilter = null;
    }
  }

  var uidCounter = 0;

  /**
   * The class that maps to the DOM MutationObserver interface.
   * @param {Function} callback.
   * @constructor
   */
  function MutationObserver(callback) {
    this.callback_ = callback;
    this.nodes_ = [];
    this.records_ = [];
    this.uid_ = ++uidCounter;

    // This will leak. There is no way to implement this without WeakRefs :'(
    globalMutationObservers.push(this);
  }

  MutationObserver.prototype = {
    // http://dom.spec.whatwg.org/#dom-mutationobserver-observe
    observe: function(target, options) {
      target = wrapIfNeeded(target);

      var newOptions = new MutationObserverOptions(options);

      // 6.
      var registration;
      var registrations = registrationsTable.get(target);
      if (!registrations)
        registrationsTable.set(target, registrations = []);

      for (var i = 0; i < registrations.length; i++) {
        if (registrations[i].observer === this) {
          registration = registrations[i];
          // 6.1.
          registration.removeTransientObservers();
          // 6.2.
          registration.options = newOptions;
        }
      }

      // 7.
      if (!registration) {
        registration = new Registration(this, target, newOptions);
        registrations.push(registration);
        this.nodes_.push(target);
      }
    },

    // http://dom.spec.whatwg.org/#dom-mutationobserver-disconnect
    disconnect: function() {
      this.nodes_.forEach(function(node) {
        var registrations = registrationsTable.get(node);
        for (var i = 0; i < registrations.length; i++) {
          var registration = registrations[i];
          if (registration.observer === this) {
            registrations.splice(i, 1);
            // Each node can only have one registered observer associated with
            // this observer.
            break;
          }
        }
      }, this);
      this.records_ = [];
    },

    takeRecords: function() {
      var copyOfRecords = this.records_;
      this.records_ = [];
      return copyOfRecords;
    }
  };

  /**
   * Class used to represent a registered observer.
   * @param {MutationObserver} observer
   * @param {Node} target
   * @param {MutationObserverOptions} options
   * @constructor
   */
  function Registration(observer, target, options) {
    this.observer = observer;
    this.target = target;
    this.options = options;
    this.transientObservedNodes = [];
  }

  Registration.prototype = {
    /**
     * Adds a transient observer on node. The transient observer gets removed
     * next time we deliver the change records.
     * @param {Node} node
     */
    addTransientObserver: function(node) {
      // Don't add transient observers on the target itself. We already have all
      // the required listeners set up on the target.
      if (node === this.target)
        return;

      this.transientObservedNodes.push(node);
      var registrations = registrationsTable.get(node);
      if (!registrations)
        registrationsTable.set(node, registrations = []);

      // We know that registrations does not contain this because we already
      // checked if node === this.target.
      registrations.push(this);
    },

    removeTransientObservers: function() {
      var transientObservedNodes = this.transientObservedNodes;
      this.transientObservedNodes = [];

      for (var i = 0; i < transientObservedNodes.length; i++) {
        var node = transientObservedNodes[i];
        var registrations = registrationsTable.get(node);
        for (var j = 0; j < registrations.length; j++) {
          if (registrations[j] === this) {
            registrations.splice(j, 1);
            // Each node can only have one registered observer associated with
            // this observer.
            break;
          }
        }
      }
    }
  };

  scope.enqueueMutation = enqueueMutation;
  scope.registerTransientObservers = registerTransientObservers;
  scope.wrappers.MutationObserver = MutationObserver;
  scope.wrappers.MutationRecord = MutationRecord;

})(window.ShadowDOMPolyfill);

/**
 * Copyright 2014 The Polymer Authors. All rights reserved.
 * Use of this source code is goverened by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {
  'use strict';

  /**
   * A tree scope represents the root of a tree. All nodes in a tree point to
   * the same TreeScope object. The tree scope of a node get set the first time
   * it is accessed or when a node is added or remove to a tree.
   * @constructor
   */
  function TreeScope(root, parent) {
    this.root = root;
    this.parent = parent;
  }

  TreeScope.prototype = {
    get renderer() {
      if (this.root instanceof scope.wrappers.ShadowRoot) {
        return scope.getRendererForHost(this.root.host);
      }
      return null;
    },

    contains: function(treeScope) {
      for (; treeScope; treeScope = treeScope.parent) {
        if (treeScope === this)
          return true;
      }
      return false;
    }
  };

  function setTreeScope(node, treeScope) {
    if (node.treeScope_ !== treeScope) {
      node.treeScope_ = treeScope;
      for (var sr = node.shadowRoot; sr; sr = sr.olderShadowRoot) {
        sr.treeScope_.parent = treeScope;
      }
      for (var child = node.firstChild; child; child = child.nextSibling) {
        setTreeScope(child, treeScope);
      }
    }
  }

  function getTreeScope(node) {
    if (node.treeScope_)
      return node.treeScope_;
    var parent = node.parentNode;
    var treeScope;
    if (parent)
      treeScope = getTreeScope(parent);
    else
      treeScope = new TreeScope(node, null);
    return node.treeScope_ = treeScope;
  }

  scope.TreeScope = TreeScope;
  scope.getTreeScope = getTreeScope;
  scope.setTreeScope = setTreeScope;

})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var forwardMethodsToWrapper = scope.forwardMethodsToWrapper;
  var getTreeScope = scope.getTreeScope;
  var mixin = scope.mixin;
  var registerWrapper = scope.registerWrapper;
  var unwrap = scope.unwrap;
  var wrap = scope.wrap;
  var wrappers = scope.wrappers;

  var wrappedFuns = new WeakMap();
  var listenersTable = new WeakMap();
  var handledEventsTable = new WeakMap();
  var currentlyDispatchingEvents = new WeakMap();
  var targetTable = new WeakMap();
  var currentTargetTable = new WeakMap();
  var relatedTargetTable = new WeakMap();
  var eventPhaseTable = new WeakMap();
  var stopPropagationTable = new WeakMap();
  var stopImmediatePropagationTable = new WeakMap();
  var eventHandlersTable = new WeakMap();
  var eventPathTable = new WeakMap();

  function isShadowRoot(node) {
    return node instanceof wrappers.ShadowRoot;
  }

  function isInsertionPoint(node) {
    var localName = node.localName;
    return localName === 'content' || localName === 'shadow';
  }

  function isShadowHost(node) {
    return !!node.shadowRoot;
  }

  function getEventParent(node) {
    var dv;
    return node.parentNode || (dv = node.defaultView) && wrap(dv) || null;
  }

  // https://dvcs.w3.org/hg/webcomponents/raw-file/tip/spec/shadow/index.html#dfn-adjusted-parent
  function calculateParents(node, context, ancestors) {
    if (ancestors.length)
      return ancestors.shift();

    // 1.
    if (isShadowRoot(node))
      return getInsertionParent(node) || node.host;

    // 2.
    var eventParents = scope.eventParentsTable.get(node);
    if (eventParents) {
      // Copy over the remaining event parents for next iteration.
      for (var i = 1; i < eventParents.length; i++) {
        ancestors[i - 1] = eventParents[i];
      }
      return eventParents[0];
    }

    // 3.
    if (context && isInsertionPoint(node)) {
      var parentNode = node.parentNode;
      if (parentNode && isShadowHost(parentNode)) {
        var trees = scope.getShadowTrees(parentNode);
        var p = getInsertionParent(context);
        for (var i = 0; i < trees.length; i++) {
          if (trees[i].contains(p))
            return p;
        }
      }
    }

    return getEventParent(node);
  }

  // https://dvcs.w3.org/hg/webcomponents/raw-file/tip/spec/shadow/index.html#event-retargeting
  function retarget(node) {
    var stack = [];  // 1.
    var ancestor = node;  // 2.
    var targets = [];
    var ancestors = [];
    while (ancestor) {  // 3.
      var context = null;  // 3.2.
      // TODO(arv): Change order of these. If the stack is empty we always end
      // up pushing ancestor, no matter what.
      if (isInsertionPoint(ancestor)) {  // 3.1.
        context = topMostNotInsertionPoint(stack);  // 3.1.1.
        var top = stack[stack.length - 1] || ancestor;  // 3.1.2.
        stack.push(top);
      } else if (!stack.length) {
        stack.push(ancestor);  // 3.3.
      }
      var target = stack[stack.length - 1];  // 3.4.
      targets.push({target: target, currentTarget: ancestor});  // 3.5.
      if (isShadowRoot(ancestor))  // 3.6.
        stack.pop();  // 3.6.1.

      ancestor = calculateParents(ancestor, context, ancestors);  // 3.7.
    }
    return targets;
  }

  function topMostNotInsertionPoint(stack) {
    for (var i = stack.length - 1; i >= 0; i--) {
      if (!isInsertionPoint(stack[i]))
        return stack[i];
    }
    return null;
  }

  // https://dvcs.w3.org/hg/webcomponents/raw-file/tip/spec/shadow/index.html#dfn-adjusted-related-target
  function adjustRelatedTarget(target, related) {
    var ancestors = [];
    while (target) {  // 3.
      var stack = [];  // 3.1.
      var ancestor = related;  // 3.2.
      var last = undefined;  // 3.3. Needs to be reset every iteration.
      while (ancestor) {
        var context = null;
        if (!stack.length) {
          stack.push(ancestor);
        } else {
          if (isInsertionPoint(ancestor)) {  // 3.4.3.
            context = topMostNotInsertionPoint(stack);
            // isDistributed is more general than checking whether last is
            // assigned into ancestor.
            if (isDistributed(last)) {  // 3.4.3.2.
              var head = stack[stack.length - 1];
              stack.push(head);
            }
          }
        }

        if (inSameTree(ancestor, target))  // 3.4.4.
          return stack[stack.length - 1];

        if (isShadowRoot(ancestor))  // 3.4.5.
          stack.pop();

        last = ancestor;  // 3.4.6.
        ancestor = calculateParents(ancestor, context, ancestors);  // 3.4.7.
      }
      if (isShadowRoot(target))  // 3.5.
        target = target.host;
      else
        target = target.parentNode;  // 3.6.
    }
  }

  function getInsertionParent(node) {
    return scope.insertionParentTable.get(node);
  }

  function isDistributed(node) {
    return getInsertionParent(node);
  }

  function inSameTree(a, b) {
    return getTreeScope(a) === getTreeScope(b);
  }

  function dispatchOriginalEvent(originalEvent) {
    // Make sure this event is only dispatched once.
    if (handledEventsTable.get(originalEvent))
      return;
    handledEventsTable.set(originalEvent, true);
    dispatchEvent(wrap(originalEvent), wrap(originalEvent.target));
  }

  function isLoadLikeEvent(event) {
    switch (event.type) {
      case 'beforeunload':
      case 'load':
      case 'unload':
        return true;
    }
    return false;
  }

  function dispatchEvent(event, originalWrapperTarget) {
    if (currentlyDispatchingEvents.get(event))
      throw new Error('InvalidStateError')
    currentlyDispatchingEvents.set(event, true);

    // Render to ensure that the event path is correct.
    scope.renderAllPending();
    var eventPath = retarget(originalWrapperTarget);

    // For window "load" events the "load" event is dispatched at the window but
    // the target is set to the document.
    //
    // http://www.whatwg.org/specs/web-apps/current-work/multipage/the-end.html#the-end
    //
    // TODO(arv): Find a less hacky way to do this.
    if (eventPath.length === 2 &&
        eventPath[0].target instanceof wrappers.Document &&
        isLoadLikeEvent(event)) {
      eventPath.shift();
    }

    eventPathTable.set(event, eventPath);

    if (dispatchCapturing(event, eventPath)) {
      if (dispatchAtTarget(event, eventPath)) {
        dispatchBubbling(event, eventPath);
      }
    }

    eventPhaseTable.set(event, Event.NONE);
    currentTargetTable.delete(event, null);
    currentlyDispatchingEvents.delete(event);

    return event.defaultPrevented;
  }

  function dispatchCapturing(event, eventPath) {
    var phase;

    for (var i = eventPath.length - 1; i > 0; i--) {
      var target = eventPath[i].target;
      var currentTarget = eventPath[i].currentTarget;
      if (target === currentTarget)
        continue;

      phase = Event.CAPTURING_PHASE;
      if (!invoke(eventPath[i], event, phase))
        return false;
    }

    return true;
  }

  function dispatchAtTarget(event, eventPath) {
    var phase = Event.AT_TARGET;
    return invoke(eventPath[0], event, phase);
  }

  function dispatchBubbling(event, eventPath) {
    var bubbles = event.bubbles;
    var phase;

    for (var i = 1; i < eventPath.length; i++) {
      var target = eventPath[i].target;
      var currentTarget = eventPath[i].currentTarget;
      if (target === currentTarget)
        phase = Event.AT_TARGET;
      else if (bubbles && !stopImmediatePropagationTable.get(event))
        phase = Event.BUBBLING_PHASE;
      else
        continue;

      if (!invoke(eventPath[i], event, phase))
        return;
    }
  }

  function invoke(tuple, event, phase) {
    var target = tuple.target;
    var currentTarget = tuple.currentTarget;

    var listeners = listenersTable.get(currentTarget);
    if (!listeners)
      return true;

    if ('relatedTarget' in event) {
      var originalEvent = unwrap(event);
      var unwrappedRelatedTarget = originalEvent.relatedTarget;

      // X-Tag sets relatedTarget on a CustomEvent. If they do that there is no
      // way to have relatedTarget return the adjusted target but worse is that
      // the originalEvent might not have a relatedTarget so we hit an assert
      // when we try to wrap it.
      if (unwrappedRelatedTarget) {
        // In IE we can get objects that are not EventTargets at this point.
        // Safari does not have an EventTarget interface so revert to checking
        // for addEventListener as an approximation.
        if (unwrappedRelatedTarget instanceof Object &&
            unwrappedRelatedTarget.addEventListener) {
          var relatedTarget = wrap(unwrappedRelatedTarget);

          var adjusted = adjustRelatedTarget(currentTarget, relatedTarget);
          if (adjusted === target)
            return true;
        } else {
          adjusted = null;
        }
        relatedTargetTable.set(event, adjusted);
      }
    }

    eventPhaseTable.set(event, phase);
    var type = event.type;

    var anyRemoved = false;
    targetTable.set(event, target);
    currentTargetTable.set(event, currentTarget);

    for (var i = 0; i < listeners.length; i++) {
      var listener = listeners[i];
      if (listener.removed) {
        anyRemoved = true;
        continue;
      }

      if (listener.type !== type ||
          !listener.capture && phase === Event.CAPTURING_PHASE ||
          listener.capture && phase === Event.BUBBLING_PHASE) {
        continue;
      }

      try {
        if (typeof listener.handler === 'function')
          listener.handler.call(currentTarget, event);
        else
          listener.handler.handleEvent(event);

        if (stopImmediatePropagationTable.get(event))
          return false;

      } catch (ex) {
        if (window.onerror)
          window.onerror(ex.message);
        else
          console.error(ex, ex.stack);
      }
    }

    if (anyRemoved) {
      var copy = listeners.slice();
      listeners.length = 0;
      for (var i = 0; i < copy.length; i++) {
        if (!copy[i].removed)
          listeners.push(copy[i]);
      }
    }

    return !stopPropagationTable.get(event);
  }

  function Listener(type, handler, capture) {
    this.type = type;
    this.handler = handler;
    this.capture = Boolean(capture);
  }
  Listener.prototype = {
    equals: function(that) {
      return this.handler === that.handler && this.type === that.type &&
          this.capture === that.capture;
    },
    get removed() {
      return this.handler === null;
    },
    remove: function() {
      this.handler = null;
    }
  };

  var OriginalEvent = window.Event;
  OriginalEvent.prototype.polymerBlackList_ = {
    returnValue: true,
    // TODO(arv): keyLocation is part of KeyboardEvent but Firefox does not
    // support constructable KeyboardEvent so we keep it here for now.
    keyLocation: true
  };

  /**
   * Creates a new Event wrapper or wraps an existin native Event object.
   * @param {string|Event} type
   * @param {Object=} options
   * @constructor
   */
  function Event(type, options) {
    if (type instanceof OriginalEvent) {
      var impl = type;
      if (!OriginalBeforeUnloadEvent && impl.type === 'beforeunload')
        return new BeforeUnloadEvent(impl);
      this.impl = impl;
    } else {
      return wrap(constructEvent(OriginalEvent, 'Event', type, options));
    }
  }
  Event.prototype = {
    get target() {
      return targetTable.get(this);
    },
    get currentTarget() {
      return currentTargetTable.get(this);
    },
    get eventPhase() {
      return eventPhaseTable.get(this);
    },
    get path() {
      var nodeList = new wrappers.NodeList();
      var eventPath = eventPathTable.get(this);
      if (eventPath) {
        var index = 0;
        var lastIndex = eventPath.length - 1;
        var baseRoot = getTreeScope(currentTargetTable.get(this));

        for (var i = 0; i <= lastIndex; i++) {
          var currentTarget = eventPath[i].currentTarget;
          var currentRoot = getTreeScope(currentTarget);
          if (currentRoot.contains(baseRoot) &&
              // Make sure we do not add Window to the path.
              (i !== lastIndex || currentTarget instanceof wrappers.Node)) {
            nodeList[index++] = currentTarget;
          }
        }
        nodeList.length = index;
      }
      return nodeList;
    },
    stopPropagation: function() {
      stopPropagationTable.set(this, true);
    },
    stopImmediatePropagation: function() {
      stopPropagationTable.set(this, true);
      stopImmediatePropagationTable.set(this, true);
    }
  };
  registerWrapper(OriginalEvent, Event, document.createEvent('Event'));

  function unwrapOptions(options) {
    if (!options || !options.relatedTarget)
      return options;
    return Object.create(options, {
      relatedTarget: {value: unwrap(options.relatedTarget)}
    });
  }

  function registerGenericEvent(name, SuperEvent, prototype) {
    var OriginalEvent = window[name];
    var GenericEvent = function(type, options) {
      if (type instanceof OriginalEvent)
        this.impl = type;
      else
        return wrap(constructEvent(OriginalEvent, name, type, options));
    };
    GenericEvent.prototype = Object.create(SuperEvent.prototype);
    if (prototype)
      mixin(GenericEvent.prototype, prototype);
    if (OriginalEvent) {
      // - Old versions of Safari fails on new FocusEvent (and others?).
      // - IE does not support event constructors.
      // - createEvent('FocusEvent') throws in Firefox.
      // => Try the best practice solution first and fallback to the old way
      // if needed.
      try {
        registerWrapper(OriginalEvent, GenericEvent, new OriginalEvent('temp'));
      } catch (ex) {
        registerWrapper(OriginalEvent, GenericEvent,
                        document.createEvent(name));
      }
    }
    return GenericEvent;
  }

  var UIEvent = registerGenericEvent('UIEvent', Event);
  var CustomEvent = registerGenericEvent('CustomEvent', Event);

  var relatedTargetProto = {
    get relatedTarget() {
      var relatedTarget = relatedTargetTable.get(this);
      // relatedTarget can be null.
      if (relatedTarget !== undefined)
        return relatedTarget;
      return wrap(unwrap(this).relatedTarget);
    }
  };

  function getInitFunction(name, relatedTargetIndex) {
    return function() {
      arguments[relatedTargetIndex] = unwrap(arguments[relatedTargetIndex]);
      var impl = unwrap(this);
      impl[name].apply(impl, arguments);
    };
  }

  var mouseEventProto = mixin({
    initMouseEvent: getInitFunction('initMouseEvent', 14)
  }, relatedTargetProto);

  var focusEventProto = mixin({
    initFocusEvent: getInitFunction('initFocusEvent', 5)
  }, relatedTargetProto);

  var MouseEvent = registerGenericEvent('MouseEvent', UIEvent, mouseEventProto);
  var FocusEvent = registerGenericEvent('FocusEvent', UIEvent, focusEventProto);

  // In case the browser does not support event constructors we polyfill that
  // by calling `createEvent('Foo')` and `initFooEvent` where the arguments to
  // `initFooEvent` are derived from the registered default event init dict.
  var defaultInitDicts = Object.create(null);

  var supportsEventConstructors = (function() {
    try {
      new window.FocusEvent('focus');
    } catch (ex) {
      return false;
    }
    return true;
  })();

  /**
   * Constructs a new native event.
   */
  function constructEvent(OriginalEvent, name, type, options) {
    if (supportsEventConstructors)
      return new OriginalEvent(type, unwrapOptions(options));

    // Create the arguments from the default dictionary.
    var event = unwrap(document.createEvent(name));
    var defaultDict = defaultInitDicts[name];
    var args = [type];
    Object.keys(defaultDict).forEach(function(key) {
      var v = options != null && key in options ?
          options[key] : defaultDict[key];
      if (key === 'relatedTarget')
        v = unwrap(v);
      args.push(v);
    });
    event['init' + name].apply(event, args);
    return event;
  }

  if (!supportsEventConstructors) {
    var configureEventConstructor = function(name, initDict, superName) {
      if (superName) {
        var superDict = defaultInitDicts[superName];
        initDict = mixin(mixin({}, superDict), initDict);
      }

      defaultInitDicts[name] = initDict;
    };

    // The order of the default event init dictionary keys is important, the
    // arguments to initFooEvent is derived from that.
    configureEventConstructor('Event', {bubbles: false, cancelable: false});
    configureEventConstructor('CustomEvent', {detail: null}, 'Event');
    configureEventConstructor('UIEvent', {view: null, detail: 0}, 'Event');
    configureEventConstructor('MouseEvent', {
      screenX: 0,
      screenY: 0,
      clientX: 0,
      clientY: 0,
      ctrlKey: false,
      altKey: false,
      shiftKey: false,
      metaKey: false,
      button: 0,
      relatedTarget: null
    }, 'UIEvent');
    configureEventConstructor('FocusEvent', {relatedTarget: null}, 'UIEvent');
  }

  // Safari 7 does not yet have BeforeUnloadEvent.
  // https://bugs.webkit.org/show_bug.cgi?id=120849
  var OriginalBeforeUnloadEvent = window.BeforeUnloadEvent;

  function BeforeUnloadEvent(impl) {
    Event.call(this, impl);
  }
  BeforeUnloadEvent.prototype = Object.create(Event.prototype);
  mixin(BeforeUnloadEvent.prototype, {
    get returnValue() {
      return this.impl.returnValue;
    },
    set returnValue(v) {
      this.impl.returnValue = v;
    }
  });

  if (OriginalBeforeUnloadEvent)
    registerWrapper(OriginalBeforeUnloadEvent, BeforeUnloadEvent);

  function isValidListener(fun) {
    if (typeof fun === 'function')
      return true;
    return fun && fun.handleEvent;
  }

  function isMutationEvent(type) {
    switch (type) {
      case 'DOMAttrModified':
      case 'DOMAttributeNameChanged':
      case 'DOMCharacterDataModified':
      case 'DOMElementNameChanged':
      case 'DOMNodeInserted':
      case 'DOMNodeInsertedIntoDocument':
      case 'DOMNodeRemoved':
      case 'DOMNodeRemovedFromDocument':
      case 'DOMSubtreeModified':
        return true;
    }
    return false;
  }

  var OriginalEventTarget = window.EventTarget;

  /**
   * This represents a wrapper for an EventTarget.
   * @param {!EventTarget} impl The original event target.
   * @constructor
   */
  function EventTarget(impl) {
    this.impl = impl;
  }

  // Node and Window have different internal type checks in WebKit so we cannot
  // use the same method as the original function.
  var methodNames = [
    'addEventListener',
    'removeEventListener',
    'dispatchEvent'
  ];

  [Node, Window].forEach(function(constructor) {
    var p = constructor.prototype;
    methodNames.forEach(function(name) {
      Object.defineProperty(p, name + '_', {value: p[name]});
    });
  });

  function getTargetToListenAt(wrapper) {
    if (wrapper instanceof wrappers.ShadowRoot)
      wrapper = wrapper.host;
    return unwrap(wrapper);
  }

  EventTarget.prototype = {
    addEventListener: function(type, fun, capture) {
      if (!isValidListener(fun) || isMutationEvent(type))
        return;

      var listener = new Listener(type, fun, capture);
      var listeners = listenersTable.get(this);
      if (!listeners) {
        listeners = [];
        listenersTable.set(this, listeners);
      } else {
        // Might have a duplicate.
        for (var i = 0; i < listeners.length; i++) {
          if (listener.equals(listeners[i]))
            return;
        }
      }

      listeners.push(listener);

      var target = getTargetToListenAt(this);
      target.addEventListener_(type, dispatchOriginalEvent, true);
    },
    removeEventListener: function(type, fun, capture) {
      capture = Boolean(capture);
      var listeners = listenersTable.get(this);
      if (!listeners)
        return;
      var count = 0, found = false;
      for (var i = 0; i < listeners.length; i++) {
        if (listeners[i].type === type && listeners[i].capture === capture) {
          count++;
          if (listeners[i].handler === fun) {
            found = true;
            listeners[i].remove();
          }
        }
      }

      if (found && count === 1) {
        var target = getTargetToListenAt(this);
        target.removeEventListener_(type, dispatchOriginalEvent, true);
      }
    },
    dispatchEvent: function(event) {
      // We want to use the native dispatchEvent because it triggers the default
      // actions (like checking a checkbox). However, if there are no listeners
      // in the composed tree then there are no events that will trigger and
      // listeners in the non composed tree that are part of the event path are
      // not notified.
      //
      // If we find out that there are no listeners in the composed tree we add
      // a temporary listener to the target which makes us get called back even
      // in that case.

      var nativeEvent = unwrap(event);
      var eventType = nativeEvent.type;

      // Allow dispatching the same event again. This is safe because if user
      // code calls this during an existing dispatch of the same event the
      // native dispatchEvent throws (that is required by the spec).
      handledEventsTable.set(nativeEvent, false);

      // Force rendering since we prefer native dispatch and that works on the
      // composed tree.
      scope.renderAllPending();

      var tempListener;
      if (!hasListenerInAncestors(this, eventType)) {
        tempListener = function() {};
        this.addEventListener(eventType, tempListener, true);
      }

      try {
        return unwrap(this).dispatchEvent_(nativeEvent);
      } finally {
        if (tempListener)
          this.removeEventListener(eventType, tempListener, true);
      }
    }
  };

  function hasListener(node, type) {
    var listeners = listenersTable.get(node);
    if (listeners) {
      for (var i = 0; i < listeners.length; i++) {
        if (!listeners[i].removed && listeners[i].type === type)
          return true;
      }
    }
    return false;
  }

  function hasListenerInAncestors(target, type) {
    for (var node = unwrap(target); node; node = node.parentNode) {
      if (hasListener(wrap(node), type))
        return true;
    }
    return false;
  }

  if (OriginalEventTarget)
    registerWrapper(OriginalEventTarget, EventTarget);

  function wrapEventTargetMethods(constructors) {
    forwardMethodsToWrapper(constructors, methodNames);
  }

  var originalElementFromPoint = document.elementFromPoint;

  function elementFromPoint(self, document, x, y) {
    scope.renderAllPending();

    var element = wrap(originalElementFromPoint.call(document.impl, x, y));
    var targets = retarget(element, this)
    for (var i = 0; i < targets.length; i++) {
      var target = targets[i];
      if (target.currentTarget === self)
        return target.target;
    }
    return null;
  }

  /**
   * Returns a function that is to be used as a getter for `onfoo` properties.
   * @param {string} name
   * @return {Function}
   */
  function getEventHandlerGetter(name) {
    return function() {
      var inlineEventHandlers = eventHandlersTable.get(this);
      return inlineEventHandlers && inlineEventHandlers[name] &&
          inlineEventHandlers[name].value || null;
     };
  }

  /**
   * Returns a function that is to be used as a setter for `onfoo` properties.
   * @param {string} name
   * @return {Function}
   */
  function getEventHandlerSetter(name) {
    var eventType = name.slice(2);
    return function(value) {
      var inlineEventHandlers = eventHandlersTable.get(this);
      if (!inlineEventHandlers) {
        inlineEventHandlers = Object.create(null);
        eventHandlersTable.set(this, inlineEventHandlers);
      }

      var old = inlineEventHandlers[name];
      if (old)
        this.removeEventListener(eventType, old.wrapped, false);

      if (typeof value === 'function') {
        var wrapped = function(e) {
          var rv = value.call(this, e);
          if (rv === false)
            e.preventDefault();
          else if (name === 'onbeforeunload' && typeof rv === 'string')
            e.returnValue = rv;
          // mouseover uses true for preventDefault but preventDefault for
          // mouseover is ignored by browsers these day.
        };

        this.addEventListener(eventType, wrapped, false);
        inlineEventHandlers[name] = {
          value: value,
          wrapped: wrapped
        };
      }
    };
  }

  scope.adjustRelatedTarget = adjustRelatedTarget;
  scope.elementFromPoint = elementFromPoint;
  scope.getEventHandlerGetter = getEventHandlerGetter;
  scope.getEventHandlerSetter = getEventHandlerSetter;
  scope.wrapEventTargetMethods = wrapEventTargetMethods;
  scope.wrappers.BeforeUnloadEvent = BeforeUnloadEvent;
  scope.wrappers.CustomEvent = CustomEvent;
  scope.wrappers.Event = Event;
  scope.wrappers.EventTarget = EventTarget;
  scope.wrappers.FocusEvent = FocusEvent;
  scope.wrappers.MouseEvent = MouseEvent;
  scope.wrappers.UIEvent = UIEvent;

})(window.ShadowDOMPolyfill);

// Copyright 2012 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var wrap = scope.wrap;

  function nonEnum(obj, prop) {
    Object.defineProperty(obj, prop, {enumerable: false});
  }

  function NodeList() {
    this.length = 0;
    nonEnum(this, 'length');
  }
  NodeList.prototype = {
    item: function(index) {
      return this[index];
    }
  };
  nonEnum(NodeList.prototype, 'item');

  function wrapNodeList(list) {
    if (list == null)
      return list;
    var wrapperList = new NodeList();
    for (var i = 0, length = list.length; i < length; i++) {
      wrapperList[i] = wrap(list[i]);
    }
    wrapperList.length = length;
    return wrapperList;
  }

  function addWrapNodeListMethod(wrapperConstructor, name) {
    wrapperConstructor.prototype[name] = function() {
      return wrapNodeList(this.impl[name].apply(this.impl, arguments));
    };
  }

  scope.wrappers.NodeList = NodeList;
  scope.addWrapNodeListMethod = addWrapNodeListMethod;
  scope.wrapNodeList = wrapNodeList;

})(window.ShadowDOMPolyfill);

/*
 * Copyright 2014 The Polymer Authors. All rights reserved.
 * Use of this source code is goverened by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {
  'use strict';

  // TODO(arv): Implement.

  scope.wrapHTMLCollection = scope.wrapNodeList;
  scope.wrappers.HTMLCollection = scope.wrappers.NodeList;

})(window.ShadowDOMPolyfill);

/**
 * Copyright 2012 The Polymer Authors. All rights reserved.
 * Use of this source code is goverened by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {
  'use strict';

  var EventTarget = scope.wrappers.EventTarget;
  var NodeList = scope.wrappers.NodeList;
  var TreeScope = scope.TreeScope;
  var assert = scope.assert;
  var defineWrapGetter = scope.defineWrapGetter;
  var enqueueMutation = scope.enqueueMutation;
  var getTreeScope = scope.getTreeScope;
  var isWrapper = scope.isWrapper;
  var mixin = scope.mixin;
  var registerTransientObservers = scope.registerTransientObservers;
  var registerWrapper = scope.registerWrapper;
  var setTreeScope = scope.setTreeScope;
  var unwrap = scope.unwrap;
  var unwrapIfNeeded = scope.unwrapIfNeeded;
  var wrap = scope.wrap;
  var wrapIfNeeded = scope.wrapIfNeeded;
  var wrappers = scope.wrappers;

  function assertIsNodeWrapper(node) {
    assert(node instanceof Node);
  }

  function createOneElementNodeList(node) {
    var nodes = new NodeList();
    nodes[0] = node;
    nodes.length = 1;
    return nodes;
  }

  var surpressMutations = false;

  /**
   * Called before node is inserted into a node to enqueue its removal from its
   * old parent.
   * @param {!Node} node The node that is about to be removed.
   * @param {!Node} parent The parent node that the node is being removed from.
   * @param {!NodeList} nodes The collected nodes.
   */
  function enqueueRemovalForInsertedNodes(node, parent, nodes) {
    enqueueMutation(parent, 'childList', {
      removedNodes: nodes,
      previousSibling: node.previousSibling,
      nextSibling: node.nextSibling
    });
  }

  function enqueueRemovalForInsertedDocumentFragment(df, nodes) {
    enqueueMutation(df, 'childList', {
      removedNodes: nodes
    });
  }

  /**
   * Collects nodes from a DocumentFragment or a Node for removal followed
   * by an insertion.
   *
   * This updates the internal pointers for node, previousNode and nextNode.
   */
  function collectNodes(node, parentNode, previousNode, nextNode) {
    if (node instanceof DocumentFragment) {
      var nodes = collectNodesForDocumentFragment(node);

      // The extra loop is to work around bugs with DocumentFragments in IE.
      surpressMutations = true;
      for (var i = nodes.length - 1; i >= 0; i--) {
        node.removeChild(nodes[i]);
        nodes[i].parentNode_ = parentNode;
      }
      surpressMutations = false;

      for (var i = 0; i < nodes.length; i++) {
        nodes[i].previousSibling_ = nodes[i - 1] || previousNode;
        nodes[i].nextSibling_ = nodes[i + 1] || nextNode;
      }

      if (previousNode)
        previousNode.nextSibling_ = nodes[0];
      if (nextNode)
        nextNode.previousSibling_ = nodes[nodes.length - 1];

      return nodes;
    }

    var nodes = createOneElementNodeList(node);
    var oldParent = node.parentNode;
    if (oldParent) {
      // This will enqueue the mutation record for the removal as needed.
      oldParent.removeChild(node);
    }

    node.parentNode_ = parentNode;
    node.previousSibling_ = previousNode;
    node.nextSibling_ = nextNode;
    if (previousNode)
      previousNode.nextSibling_ = node;
    if (nextNode)
      nextNode.previousSibling_ = node;

    return nodes;
  }

  function collectNodesNative(node) {
    if (node instanceof DocumentFragment)
      return collectNodesForDocumentFragment(node);

    var nodes = createOneElementNodeList(node);
    var oldParent = node.parentNode;
    if (oldParent)
      enqueueRemovalForInsertedNodes(node, oldParent, nodes);
    return nodes;
  }

  function collectNodesForDocumentFragment(node) {
    var nodes = new NodeList();
    var i = 0;
    for (var child = node.firstChild; child; child = child.nextSibling) {
      nodes[i++] = child;
    }
    nodes.length = i;
    enqueueRemovalForInsertedDocumentFragment(node, nodes);
    return nodes;
  }

  function snapshotNodeList(nodeList) {
    // NodeLists are not live at the moment so just return the same object.
    return nodeList;
  }

  // http://dom.spec.whatwg.org/#node-is-inserted
  function nodeWasAdded(node, treeScope) {
    setTreeScope(node, treeScope);
    node.nodeIsInserted_();
  }

  function nodesWereAdded(nodes, parent) {
    var treeScope = getTreeScope(parent);
    for (var i = 0; i < nodes.length; i++) {
      nodeWasAdded(nodes[i], treeScope);
    }
  }

  // http://dom.spec.whatwg.org/#node-is-removed
  function nodeWasRemoved(node) {
    setTreeScope(node, new TreeScope(node, null));
  }

  function nodesWereRemoved(nodes) {
    for (var i = 0; i < nodes.length; i++) {
      nodeWasRemoved(nodes[i]);
    }
  }

  function ensureSameOwnerDocument(parent, child) {
    var ownerDoc = parent.nodeType === Node.DOCUMENT_NODE ?
        parent : parent.ownerDocument;
    if (ownerDoc !== child.ownerDocument)
      ownerDoc.adoptNode(child);
  }

  function adoptNodesIfNeeded(owner, nodes) {
    if (!nodes.length)
      return;

    var ownerDoc = owner.ownerDocument;

    // All nodes have the same ownerDocument when we get here.
    if (ownerDoc === nodes[0].ownerDocument)
      return;

    for (var i = 0; i < nodes.length; i++) {
      scope.adoptNodeNoRemove(nodes[i], ownerDoc);
    }
  }

  function unwrapNodesForInsertion(owner, nodes) {
    adoptNodesIfNeeded(owner, nodes);
    var length = nodes.length;

    if (length === 1)
      return unwrap(nodes[0]);

    var df = unwrap(owner.ownerDocument.createDocumentFragment());
    for (var i = 0; i < length; i++) {
      df.appendChild(unwrap(nodes[i]));
    }
    return df;
  }

  function clearChildNodes(wrapper) {
    if (wrapper.firstChild_ !== undefined) {
      var child = wrapper.firstChild_;
      while (child) {
        var tmp = child;
        child = child.nextSibling_;
        tmp.parentNode_ = tmp.previousSibling_ = tmp.nextSibling_ = undefined;
      }
    }
    wrapper.firstChild_ = wrapper.lastChild_ = undefined;
  }

  function removeAllChildNodes(wrapper) {
    if (wrapper.invalidateShadowRenderer()) {
      var childWrapper = wrapper.firstChild;
      while (childWrapper) {
        assert(childWrapper.parentNode === wrapper);
        var nextSibling = childWrapper.nextSibling;
        var childNode = unwrap(childWrapper);
        var parentNode = childNode.parentNode;
        if (parentNode)
          originalRemoveChild.call(parentNode, childNode);
        childWrapper.previousSibling_ = childWrapper.nextSibling_ =
            childWrapper.parentNode_ = null;
        childWrapper = nextSibling;
      }
      wrapper.firstChild_ = wrapper.lastChild_ = null;
    } else {
      var node = unwrap(wrapper);
      var child = node.firstChild;
      var nextSibling;
      while (child) {
        nextSibling = child.nextSibling;
        originalRemoveChild.call(node, child);
        child = nextSibling;
      }
    }
  }

  function invalidateParent(node) {
    var p = node.parentNode;
    return p && p.invalidateShadowRenderer();
  }

  function cleanupNodes(nodes) {
    for (var i = 0, n; i < nodes.length; i++) {
      n = nodes[i];
      n.parentNode.removeChild(n);
    }
  }

  var originalImportNode = document.importNode;
  var originalCloneNode = window.Node.prototype.cloneNode;

  function cloneNode(node, deep, opt_doc) {
    var clone;
    if (opt_doc)
      clone = wrap(originalImportNode.call(opt_doc, node.impl, false));
    else
      clone = wrap(originalCloneNode.call(node.impl, false));

    if (deep) {
      for (var child = node.firstChild; child; child = child.nextSibling) {
        clone.appendChild(cloneNode(child, true, opt_doc));
      }

      if (node instanceof wrappers.HTMLTemplateElement) {
        var cloneContent = clone.content;
        for (var child = node.content.firstChild;
             child;
             child = child.nextSibling) {
         cloneContent.appendChild(cloneNode(child, true, opt_doc));
        }
      }
    }
    // TODO(arv): Some HTML elements also clone other data like value.
    return clone;
  }

  function contains(self, child) {
    if (!child || getTreeScope(self) !== getTreeScope(child))
      return false;

    for (var node = child; node; node = node.parentNode) {
      if (node === self)
        return true;
    }
    return false;
  }

  var OriginalNode = window.Node;

  /**
   * This represents a wrapper of a native DOM node.
   * @param {!Node} original The original DOM node, aka, the visual DOM node.
   * @constructor
   * @extends {EventTarget}
   */
  function Node(original) {
    assert(original instanceof OriginalNode);

    EventTarget.call(this, original);

    // These properties are used to override the visual references with the
    // logical ones. If the value is undefined it means that the logical is the
    // same as the visual.

    /**
     * @type {Node|undefined}
     * @private
     */
    this.parentNode_ = undefined;

    /**
     * @type {Node|undefined}
     * @private
     */
    this.firstChild_ = undefined;

    /**
     * @type {Node|undefined}
     * @private
     */
    this.lastChild_ = undefined;

    /**
     * @type {Node|undefined}
     * @private
     */
    this.nextSibling_ = undefined;

    /**
     * @type {Node|undefined}
     * @private
     */
    this.previousSibling_ = undefined;

    this.treeScope_ = undefined;
  }

  var OriginalDocumentFragment = window.DocumentFragment;
  var originalAppendChild = OriginalNode.prototype.appendChild;
  var originalCompareDocumentPosition =
      OriginalNode.prototype.compareDocumentPosition;
  var originalInsertBefore = OriginalNode.prototype.insertBefore;
  var originalRemoveChild = OriginalNode.prototype.removeChild;
  var originalReplaceChild = OriginalNode.prototype.replaceChild;

  var isIe = /Trident/.test(navigator.userAgent);

  var removeChildOriginalHelper = isIe ?
      function(parent, child) {
        try {
          originalRemoveChild.call(parent, child);
        } catch (ex) {
          if (!(parent instanceof OriginalDocumentFragment))
            throw ex;
        }
      } :
      function(parent, child) {
        originalRemoveChild.call(parent, child);
      };

  Node.prototype = Object.create(EventTarget.prototype);
  mixin(Node.prototype, {
    appendChild: function(childWrapper) {
      return this.insertBefore(childWrapper, null);
    },

    insertBefore: function(childWrapper, refWrapper) {
      assertIsNodeWrapper(childWrapper);

      var refNode;
      if (refWrapper) {
        if (isWrapper(refWrapper)) {
          refNode = unwrap(refWrapper);
        } else {
          refNode = refWrapper;
          refWrapper = wrap(refNode);
        }
      } else {
        refWrapper = null;
        refNode = null;
      }

      refWrapper && assert(refWrapper.parentNode === this);

      var nodes;
      var previousNode =
          refWrapper ? refWrapper.previousSibling : this.lastChild;

      var useNative = !this.invalidateShadowRenderer() &&
                      !invalidateParent(childWrapper);

      if (useNative)
        nodes = collectNodesNative(childWrapper);
      else
        nodes = collectNodes(childWrapper, this, previousNode, refWrapper);

      if (useNative) {
        ensureSameOwnerDocument(this, childWrapper);
        clearChildNodes(this);
        originalInsertBefore.call(this.impl, unwrap(childWrapper), refNode);
      } else {
        if (!previousNode)
          this.firstChild_ = nodes[0];
        if (!refWrapper)
          this.lastChild_ = nodes[nodes.length - 1];

        var parentNode = refNode ? refNode.parentNode : this.impl;

        // insertBefore refWrapper no matter what the parent is?
        if (parentNode) {
          originalInsertBefore.call(parentNode,
              unwrapNodesForInsertion(this, nodes), refNode);
        } else {
          adoptNodesIfNeeded(this, nodes);
        }
      }

      enqueueMutation(this, 'childList', {
        addedNodes: nodes,
        nextSibling: refWrapper,
        previousSibling: previousNode
      });

      nodesWereAdded(nodes, this);

      return childWrapper;
    },

    removeChild: function(childWrapper) {
      assertIsNodeWrapper(childWrapper);
      if (childWrapper.parentNode !== this) {
        // IE has invalid DOM trees at times.
        var found = false;
        var childNodes = this.childNodes;
        for (var ieChild = this.firstChild; ieChild;
             ieChild = ieChild.nextSibling) {
          if (ieChild === childWrapper) {
            found = true;
            break;
          }
        }
        if (!found) {
          // TODO(arv): DOMException
          throw new Error('NotFoundError');
        }
      }

      var childNode = unwrap(childWrapper);
      var childWrapperNextSibling = childWrapper.nextSibling;
      var childWrapperPreviousSibling = childWrapper.previousSibling;

      if (this.invalidateShadowRenderer()) {
        // We need to remove the real node from the DOM before updating the
        // pointers. This is so that that mutation event is dispatched before
        // the pointers have changed.
        var thisFirstChild = this.firstChild;
        var thisLastChild = this.lastChild;

        var parentNode = childNode.parentNode;
        if (parentNode)
          removeChildOriginalHelper(parentNode, childNode);

        if (thisFirstChild === childWrapper)
          this.firstChild_ = childWrapperNextSibling;
        if (thisLastChild === childWrapper)
          this.lastChild_ = childWrapperPreviousSibling;
        if (childWrapperPreviousSibling)
          childWrapperPreviousSibling.nextSibling_ = childWrapperNextSibling;
        if (childWrapperNextSibling) {
          childWrapperNextSibling.previousSibling_ =
              childWrapperPreviousSibling;
        }

        childWrapper.previousSibling_ = childWrapper.nextSibling_ =
            childWrapper.parentNode_ = undefined;
      } else {
        clearChildNodes(this);
        removeChildOriginalHelper(this.impl, childNode);
      }

      if (!surpressMutations) {
        enqueueMutation(this, 'childList', {
          removedNodes: createOneElementNodeList(childWrapper),
          nextSibling: childWrapperNextSibling,
          previousSibling: childWrapperPreviousSibling
        });
      }

      registerTransientObservers(this, childWrapper);

      return childWrapper;
    },

    replaceChild: function(newChildWrapper, oldChildWrapper) {
      assertIsNodeWrapper(newChildWrapper);

      var oldChildNode;
      if (isWrapper(oldChildWrapper)) {
        oldChildNode = unwrap(oldChildWrapper);
      } else {
        oldChildNode = oldChildWrapper;
        oldChildWrapper = wrap(oldChildNode);
      }

      if (oldChildWrapper.parentNode !== this) {
        // TODO(arv): DOMException
        throw new Error('NotFoundError');
      }

      var nextNode = oldChildWrapper.nextSibling;
      var previousNode = oldChildWrapper.previousSibling;
      var nodes;

      var useNative = !this.invalidateShadowRenderer() &&
                      !invalidateParent(newChildWrapper);

      if (useNative) {
        nodes = collectNodesNative(newChildWrapper);
      } else {
        if (nextNode === newChildWrapper)
          nextNode = newChildWrapper.nextSibling;
        nodes = collectNodes(newChildWrapper, this, previousNode, nextNode);
      }

      if (!useNative) {
        if (this.firstChild === oldChildWrapper)
          this.firstChild_ = nodes[0];
        if (this.lastChild === oldChildWrapper)
          this.lastChild_ = nodes[nodes.length - 1];

        oldChildWrapper.previousSibling_ = oldChildWrapper.nextSibling_ =
            oldChildWrapper.parentNode_ = undefined;

        // replaceChild no matter what the parent is?
        if (oldChildNode.parentNode) {
          originalReplaceChild.call(
              oldChildNode.parentNode,
              unwrapNodesForInsertion(this, nodes),
              oldChildNode);
        }
      } else {
        ensureSameOwnerDocument(this, newChildWrapper);
        clearChildNodes(this);
        originalReplaceChild.call(this.impl, unwrap(newChildWrapper),
                                  oldChildNode);
      }

      enqueueMutation(this, 'childList', {
        addedNodes: nodes,
        removedNodes: createOneElementNodeList(oldChildWrapper),
        nextSibling: nextNode,
        previousSibling: previousNode
      });

      nodeWasRemoved(oldChildWrapper);
      nodesWereAdded(nodes, this);

      return oldChildWrapper;
    },

    /**
     * Called after a node was inserted. Subclasses override this to invalidate
     * the renderer as needed.
     * @private
     */
    nodeIsInserted_: function() {
      for (var child = this.firstChild; child; child = child.nextSibling) {
        child.nodeIsInserted_();
      }
    },

    hasChildNodes: function() {
      return this.firstChild !== null;
    },

    /** @type {Node} */
    get parentNode() {
      // If the parentNode has not been overridden, use the original parentNode.
      return this.parentNode_ !== undefined ?
          this.parentNode_ : wrap(this.impl.parentNode);
    },

    /** @type {Node} */
    get firstChild() {
      return this.firstChild_ !== undefined ?
          this.firstChild_ : wrap(this.impl.firstChild);
    },

    /** @type {Node} */
    get lastChild() {
      return this.lastChild_ !== undefined ?
          this.lastChild_ : wrap(this.impl.lastChild);
    },

    /** @type {Node} */
    get nextSibling() {
      return this.nextSibling_ !== undefined ?
          this.nextSibling_ : wrap(this.impl.nextSibling);
    },

    /** @type {Node} */
    get previousSibling() {
      return this.previousSibling_ !== undefined ?
          this.previousSibling_ : wrap(this.impl.previousSibling);
    },

    get parentElement() {
      var p = this.parentNode;
      while (p && p.nodeType !== Node.ELEMENT_NODE) {
        p = p.parentNode;
      }
      return p;
    },

    get textContent() {
      // TODO(arv): This should fallback to this.impl.textContent if there
      // are no shadow trees below or above the context node.
      var s = '';
      for (var child = this.firstChild; child; child = child.nextSibling) {
        if (child.nodeType != Node.COMMENT_NODE) {
          s += child.textContent;
        }
      }
      return s;
    },
    set textContent(textContent) {
      var removedNodes = snapshotNodeList(this.childNodes);

      if (this.invalidateShadowRenderer()) {
        removeAllChildNodes(this);
        if (textContent !== '') {
          var textNode = this.impl.ownerDocument.createTextNode(textContent);
          this.appendChild(textNode);
        }
      } else {
        clearChildNodes(this);
        this.impl.textContent = textContent;
      }

      var addedNodes = snapshotNodeList(this.childNodes);

      enqueueMutation(this, 'childList', {
        addedNodes: addedNodes,
        removedNodes: removedNodes
      });

      nodesWereRemoved(removedNodes);
      nodesWereAdded(addedNodes, this);
    },

    get childNodes() {
      var wrapperList = new NodeList();
      var i = 0;
      for (var child = this.firstChild; child; child = child.nextSibling) {
        wrapperList[i++] = child;
      }
      wrapperList.length = i;
      return wrapperList;
    },

    cloneNode: function(deep) {
      return cloneNode(this, deep);
    },

    contains: function(child) {
      return contains(this, wrapIfNeeded(child));
    },

    compareDocumentPosition: function(otherNode) {
      // This only wraps, it therefore only operates on the composed DOM and not
      // the logical DOM.
      return originalCompareDocumentPosition.call(this.impl,
                                                  unwrapIfNeeded(otherNode));
    },

    normalize: function() {
      var nodes = snapshotNodeList(this.childNodes);
      var remNodes = [];
      var s = '';
      var modNode;

      for (var i = 0, n; i < nodes.length; i++) {
        n = nodes[i];
        if (n.nodeType === Node.TEXT_NODE) {
          if (!modNode && !n.data.length)
            this.removeNode(n);
          else if (!modNode)
            modNode = n;
          else {
            s += n.data;
            remNodes.push(n);
          }
        } else {
          if (modNode && remNodes.length) {
            modNode.data += s;
            cleanUpNodes(remNodes);
          }
          remNodes = [];
          s = '';
          modNode = null;
          if (n.childNodes.length)
            n.normalize();
        }
      }

      // handle case where >1 text nodes are the last children
      if (modNode && remNodes.length) {
        modNode.data += s;
        cleanupNodes(remNodes);
      }
    }
  });

  defineWrapGetter(Node, 'ownerDocument');

  // We use a DocumentFragment as a base and then delete the properties of
  // DocumentFragment.prototype from the wrapper Node. Since delete makes
  // objects slow in some JS engines we recreate the prototype object.
  registerWrapper(OriginalNode, Node, document.createDocumentFragment());
  delete Node.prototype.querySelector;
  delete Node.prototype.querySelectorAll;
  Node.prototype = mixin(Object.create(EventTarget.prototype), Node.prototype);

  scope.cloneNode = cloneNode;
  scope.nodeWasAdded = nodeWasAdded;
  scope.nodeWasRemoved = nodeWasRemoved;
  scope.nodesWereAdded = nodesWereAdded;
  scope.nodesWereRemoved = nodesWereRemoved;
  scope.snapshotNodeList = snapshotNodeList;
  scope.wrappers.Node = Node;

})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  function findOne(node, selector) {
    var m, el = node.firstElementChild;
    while (el) {
      if (el.matches(selector))
        return el;
      m = findOne(el, selector);
      if (m)
        return m;
      el = el.nextElementSibling;
    }
    return null;
  }

  function findAll(node, selector, results) {
    var el = node.firstElementChild;
    while (el) {
      if (el.matches(selector))
        results[results.length++] = el;
      findAll(el, selector, results);
      el = el.nextElementSibling;
    }
    return results;
  }

  // find and findAll will only match Simple Selectors,
  // Structural Pseudo Classes are not guarenteed to be correct
  // http://www.w3.org/TR/css3-selectors/#simple-selectors

  var SelectorsInterface = {
    querySelector: function(selector) {
      return findOne(this, selector);
    },
    querySelectorAll: function(selector) {
      return findAll(this, selector, new NodeList())
    }
  };

  var GetElementsByInterface = {
    getElementsByTagName: function(tagName) {
      // TODO(arv): Check tagName?
      return this.querySelectorAll(tagName);
    },
    getElementsByClassName: function(className) {
      // TODO(arv): Check className?
      return this.querySelectorAll('.' + className);
    },
    getElementsByTagNameNS: function(ns, tagName) {
      if (ns === '*')
        return this.getElementsByTagName(tagName);

      // TODO(arv): Check tagName?
      var result = new NodeList;
      var els = this.getElementsByTagName(tagName);
      for (var i = 0, j = 0; i < els.length; i++) {
        if (els[i].namespaceURI === ns)
          result[j++] = els[i];
      }
      result.length = j;
      return result;
    }
  };

  scope.GetElementsByInterface = GetElementsByInterface;
  scope.SelectorsInterface = SelectorsInterface;

})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var NodeList = scope.wrappers.NodeList;

  function forwardElement(node) {
    while (node && node.nodeType !== Node.ELEMENT_NODE) {
      node = node.nextSibling;
    }
    return node;
  }

  function backwardsElement(node) {
    while (node && node.nodeType !== Node.ELEMENT_NODE) {
      node = node.previousSibling;
    }
    return node;
  }

  var ParentNodeInterface = {
    get firstElementChild() {
      return forwardElement(this.firstChild);
    },

    get lastElementChild() {
      return backwardsElement(this.lastChild);
    },

    get childElementCount() {
      var count = 0;
      for (var child = this.firstElementChild;
           child;
           child = child.nextElementSibling) {
        count++;
      }
      return count;
    },

    get children() {
      var wrapperList = new NodeList();
      var i = 0;
      for (var child = this.firstElementChild;
           child;
           child = child.nextElementSibling) {
        wrapperList[i++] = child;
      }
      wrapperList.length = i;
      return wrapperList;
    },

    remove: function() {
      var p = this.parentNode;
      if (p)
        p.removeChild(this);
    }
  };

  var ChildNodeInterface = {
    get nextElementSibling() {
      return forwardElement(this.nextSibling);
    },

    get previousElementSibling() {
      return backwardsElement(this.previousSibling);
    }
  };

  scope.ChildNodeInterface = ChildNodeInterface;
  scope.ParentNodeInterface = ParentNodeInterface;

})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var ChildNodeInterface = scope.ChildNodeInterface;
  var Node = scope.wrappers.Node;
  var enqueueMutation = scope.enqueueMutation;
  var mixin = scope.mixin;
  var registerWrapper = scope.registerWrapper;

  var OriginalCharacterData = window.CharacterData;

  function CharacterData(node) {
    Node.call(this, node);
  }
  CharacterData.prototype = Object.create(Node.prototype);
  mixin(CharacterData.prototype, {
    get textContent() {
      return this.data;
    },
    set textContent(value) {
      this.data = value;
    },
    get data() {
      return this.impl.data;
    },
    set data(value) {
      var oldValue = this.impl.data;
      enqueueMutation(this, 'characterData', {
        oldValue: oldValue
      });
      this.impl.data = value;
    }
  });

  mixin(CharacterData.prototype, ChildNodeInterface);

  registerWrapper(OriginalCharacterData, CharacterData,
                  document.createTextNode(''));

  scope.wrappers.CharacterData = CharacterData;
})(window.ShadowDOMPolyfill);

// Copyright 2014 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var CharacterData = scope.wrappers.CharacterData;
  var enqueueMutation = scope.enqueueMutation;
  var mixin = scope.mixin;
  var registerWrapper = scope.registerWrapper;

  function toUInt32(x) {
    return x >>> 0;
  }

  var OriginalText = window.Text;

  function Text(node) {
    CharacterData.call(this, node);
  }
  Text.prototype = Object.create(CharacterData.prototype);
  mixin(Text.prototype, {
    splitText: function(offset) {
      offset = toUInt32(offset);
      var s = this.data;
      if (offset > s.length)
        throw new Error('IndexSizeError');
      var head = s.slice(0, offset);
      var tail = s.slice(offset);
      this.data = head;
      var newTextNode = this.ownerDocument.createTextNode(tail);
      if (this.parentNode)
        this.parentNode.insertBefore(newTextNode, this.nextSibling);
      return newTextNode;
    }
  });

  registerWrapper(OriginalText, Text, document.createTextNode(''));

  scope.wrappers.Text = Text;
})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var ChildNodeInterface = scope.ChildNodeInterface;
  var GetElementsByInterface = scope.GetElementsByInterface;
  var Node = scope.wrappers.Node;
  var ParentNodeInterface = scope.ParentNodeInterface;
  var SelectorsInterface = scope.SelectorsInterface;
  var addWrapNodeListMethod = scope.addWrapNodeListMethod;
  var enqueueMutation = scope.enqueueMutation;
  var mixin = scope.mixin;
  var oneOf = scope.oneOf;
  var registerWrapper = scope.registerWrapper;
  var wrappers = scope.wrappers;

  var OriginalElement = window.Element;

  var matchesNames = [
    'matches',  // needs to come first.
    'mozMatchesSelector',
    'msMatchesSelector',
    'webkitMatchesSelector',
  ].filter(function(name) {
    return OriginalElement.prototype[name];
  });

  var matchesName = matchesNames[0];

  var originalMatches = OriginalElement.prototype[matchesName];

  function invalidateRendererBasedOnAttribute(element, name) {
    // Only invalidate if parent node is a shadow host.
    var p = element.parentNode;
    if (!p || !p.shadowRoot)
      return;

    var renderer = scope.getRendererForHost(p);
    if (renderer.dependsOnAttribute(name))
      renderer.invalidate();
  }

  function enqueAttributeChange(element, name, oldValue) {
    // This is not fully spec compliant. We should use localName (which might
    // have a different case than name) and the namespace (which requires us
    // to get the Attr object).
    enqueueMutation(element, 'attributes', {
      name: name,
      namespace: null,
      oldValue: oldValue
    });
  }

  function Element(node) {
    Node.call(this, node);
  }
  Element.prototype = Object.create(Node.prototype);
  mixin(Element.prototype, {
    createShadowRoot: function() {
      var newShadowRoot = new wrappers.ShadowRoot(this);
      this.impl.polymerShadowRoot_ = newShadowRoot;

      var renderer = scope.getRendererForHost(this);
      renderer.invalidate();

      return newShadowRoot;
    },

    get shadowRoot() {
      return this.impl.polymerShadowRoot_ || null;
    },

    setAttribute: function(name, value) {
      var oldValue = this.impl.getAttribute(name);
      this.impl.setAttribute(name, value);
      enqueAttributeChange(this, name, oldValue);
      invalidateRendererBasedOnAttribute(this, name);
    },

    removeAttribute: function(name) {
      var oldValue = this.impl.getAttribute(name);
      this.impl.removeAttribute(name);
      enqueAttributeChange(this, name, oldValue);
      invalidateRendererBasedOnAttribute(this, name);
    },

    matches: function(selector) {
      return originalMatches.call(this.impl, selector);
    }
  });

  matchesNames.forEach(function(name) {
    if (name !== 'matches') {
      Element.prototype[name] = function(selector) {
        return this.matches(selector);
      };
    }
  });

  if (OriginalElement.prototype.webkitCreateShadowRoot) {
    Element.prototype.webkitCreateShadowRoot =
        Element.prototype.createShadowRoot;
  }

  /**
   * Useful for generating the accessor pair for a property that reflects an
   * attribute.
   */
  function setterDirtiesAttribute(prototype, propertyName, opt_attrName) {
    var attrName = opt_attrName || propertyName;
    Object.defineProperty(prototype, propertyName, {
      get: function() {
        return this.impl[propertyName];
      },
      set: function(v) {
        this.impl[propertyName] = v;
        invalidateRendererBasedOnAttribute(this, attrName);
      },
      configurable: true,
      enumerable: true
    });
  }

  setterDirtiesAttribute(Element.prototype, 'id');
  setterDirtiesAttribute(Element.prototype, 'className', 'class');

  mixin(Element.prototype, ChildNodeInterface);
  mixin(Element.prototype, GetElementsByInterface);
  mixin(Element.prototype, ParentNodeInterface);
  mixin(Element.prototype, SelectorsInterface);

  registerWrapper(OriginalElement, Element,
                  document.createElementNS(null, 'x'));

  // TODO(arv): Export setterDirtiesAttribute and apply it to more bindings
  // that reflect attributes.
  scope.matchesNames = matchesNames;
  scope.wrappers.Element = Element;
})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var Element = scope.wrappers.Element;
  var defineGetter = scope.defineGetter;
  var enqueueMutation = scope.enqueueMutation;
  var mixin = scope.mixin;
  var nodesWereAdded = scope.nodesWereAdded;
  var nodesWereRemoved = scope.nodesWereRemoved;
  var registerWrapper = scope.registerWrapper;
  var snapshotNodeList = scope.snapshotNodeList;
  var unwrap = scope.unwrap;
  var wrap = scope.wrap;
  var wrappers = scope.wrappers;

  /////////////////////////////////////////////////////////////////////////////
  // innerHTML and outerHTML

  // http://www.whatwg.org/specs/web-apps/current-work/multipage/the-end.html#escapingString
  var escapeAttrRegExp = /[&\u00A0"]/g;
  var escapeDataRegExp = /[&\u00A0<>]/g;

  function escapeReplace(c) {
    switch (c) {
      case '&':
        return '&amp;';
      case '<':
        return '&lt;';
      case '>':
        return '&gt;';
      case '"':
        return '&quot;'
      case '\u00A0':
        return '&nbsp;';
    }
  }

  function escapeAttr(s) {
    return s.replace(escapeAttrRegExp, escapeReplace);
  }

  function escapeData(s) {
    return s.replace(escapeDataRegExp, escapeReplace);
  }

  function makeSet(arr) {
    var set = {};
    for (var i = 0; i < arr.length; i++) {
      set[arr[i]] = true;
    }
    return set;
  }

  // http://www.whatwg.org/specs/web-apps/current-work/#void-elements
  var voidElements = makeSet([
    'area',
    'base',
    'br',
    'col',
    'command',
    'embed',
    'hr',
    'img',
    'input',
    'keygen',
    'link',
    'meta',
    'param',
    'source',
    'track',
    'wbr'
  ]);

  var plaintextParents = makeSet([
    'style',
    'script',
    'xmp',
    'iframe',
    'noembed',
    'noframes',
    'plaintext',
    'noscript'
  ]);

  function getOuterHTML(node, parentNode) {
    switch (node.nodeType) {
      case Node.ELEMENT_NODE:
        var tagName = node.tagName.toLowerCase();
        var s = '<' + tagName;
        var attrs = node.attributes;
        for (var i = 0, attr; attr = attrs[i]; i++) {
          s += ' ' + attr.name + '="' + escapeAttr(attr.value) + '"';
        }
        s += '>';
        if (voidElements[tagName])
          return s;

        return s + getInnerHTML(node) + '</' + tagName + '>';

      case Node.TEXT_NODE:
        var data = node.data;
        if (parentNode && plaintextParents[parentNode.localName])
          return data;
        return escapeData(data);

      case Node.COMMENT_NODE:
        return '<!--' + node.data + '-->';

      default:
        console.error(node);
        throw new Error('not implemented');
    }
  }

  function getInnerHTML(node) {
    if (node instanceof wrappers.HTMLTemplateElement)
      node = node.content;

    var s = '';
    for (var child = node.firstChild; child; child = child.nextSibling) {
      s += getOuterHTML(child, node);
    }
    return s;
  }

  function setInnerHTML(node, value, opt_tagName) {
    var tagName = opt_tagName || 'div';
    node.textContent = '';
    var tempElement = unwrap(node.ownerDocument.createElement(tagName));
    tempElement.innerHTML = value;
    var firstChild;
    while (firstChild = tempElement.firstChild) {
      node.appendChild(wrap(firstChild));
    }
  }

  // IE11 does not have MSIE in the user agent string.
  var oldIe = /MSIE/.test(navigator.userAgent);

  var OriginalHTMLElement = window.HTMLElement;
  var OriginalHTMLTemplateElement = window.HTMLTemplateElement;

  function HTMLElement(node) {
    Element.call(this, node);
  }
  HTMLElement.prototype = Object.create(Element.prototype);
  mixin(HTMLElement.prototype, {
    get innerHTML() {
      return getInnerHTML(this);
    },
    set innerHTML(value) {
      // IE9 does not handle set innerHTML correctly on plaintextParents. It
      // creates element children. For example
      //
      //   scriptElement.innerHTML = '<a>test</a>'
      //
      // Creates a single HTMLAnchorElement child.
      if (oldIe && plaintextParents[this.localName]) {
        this.textContent = value;
        return;
      }

      var removedNodes = snapshotNodeList(this.childNodes);

      if (this.invalidateShadowRenderer()) {
        if (this instanceof wrappers.HTMLTemplateElement)
          setInnerHTML(this.content, value);
        else
          setInnerHTML(this, value, this.tagName);

      // If we have a non native template element we need to handle this
      // manually since setting impl.innerHTML would add the html as direct
      // children and not be moved over to the content fragment.
      } else if (!OriginalHTMLTemplateElement &&
                 this instanceof wrappers.HTMLTemplateElement) {
        setInnerHTML(this.content, value);
      } else {
        this.impl.innerHTML = value;
      }

      var addedNodes = snapshotNodeList(this.childNodes);

      enqueueMutation(this, 'childList', {
        addedNodes: addedNodes,
        removedNodes: removedNodes
      });

      nodesWereRemoved(removedNodes);
      nodesWereAdded(addedNodes, this);
    },

    get outerHTML() {
      return getOuterHTML(this, this.parentNode);
    },
    set outerHTML(value) {
      var p = this.parentNode;
      if (p) {
        p.invalidateShadowRenderer();
        var df = frag(p, value);
        p.replaceChild(df, this);
      }
    },

    insertAdjacentHTML: function(position, text) {
      var contextElement, refNode;
      switch (String(position).toLowerCase()) {
        case 'beforebegin':
          contextElement = this.parentNode;
          refNode = this;
          break;
        case 'afterend':
          contextElement = this.parentNode;
          refNode = this.nextSibling;
          break;
        case 'afterbegin':
          contextElement = this;
          refNode = this.firstChild;
          break;
        case 'beforeend':
          contextElement = this;
          refNode = null;
          break;
        default:
          return;
      }

      var df = frag(contextElement, text);
      contextElement.insertBefore(df, refNode);
    }
  });

  function frag(contextElement, html) {
    // TODO(arv): This does not work with SVG and other non HTML elements.
    var p = unwrap(contextElement.cloneNode(false));
    p.innerHTML = html;
    var df = unwrap(document.createDocumentFragment());
    var c;
    while (c = p.firstChild) {
      df.appendChild(c);
    }
    return wrap(df);
  }

  function getter(name) {
    return function() {
      scope.renderAllPending();
      return this.impl[name];
    };
  }

  function getterRequiresRendering(name) {
    defineGetter(HTMLElement, name, getter(name));
  }

  [
    'clientHeight',
    'clientLeft',
    'clientTop',
    'clientWidth',
    'offsetHeight',
    'offsetLeft',
    'offsetTop',
    'offsetWidth',
    'scrollHeight',
    'scrollWidth',
  ].forEach(getterRequiresRendering);

  function getterAndSetterRequiresRendering(name) {
    Object.defineProperty(HTMLElement.prototype, name, {
      get: getter(name),
      set: function(v) {
        scope.renderAllPending();
        this.impl[name] = v;
      },
      configurable: true,
      enumerable: true
    });
  }

  [
    'scrollLeft',
    'scrollTop',
  ].forEach(getterAndSetterRequiresRendering);

  function methodRequiresRendering(name) {
    Object.defineProperty(HTMLElement.prototype, name, {
      value: function() {
        scope.renderAllPending();
        return this.impl[name].apply(this.impl, arguments);
      },
      configurable: true,
      enumerable: true
    });
  }

  [
    'getBoundingClientRect',
    'getClientRects',
    'scrollIntoView'
  ].forEach(methodRequiresRendering);

  // HTMLElement is abstract so we use a subclass that has no members.
  registerWrapper(OriginalHTMLElement, HTMLElement,
                  document.createElement('b'));

  scope.wrappers.HTMLElement = HTMLElement;

  // TODO: Find a better way to share these two with WrapperShadowRoot.
  scope.getInnerHTML = getInnerHTML;
  scope.setInnerHTML = setInnerHTML
})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var HTMLElement = scope.wrappers.HTMLElement;
  var mixin = scope.mixin;
  var registerWrapper = scope.registerWrapper;
  var wrap = scope.wrap;

  var OriginalHTMLCanvasElement = window.HTMLCanvasElement;

  function HTMLCanvasElement(node) {
    HTMLElement.call(this, node);
  }
  HTMLCanvasElement.prototype = Object.create(HTMLElement.prototype);

  mixin(HTMLCanvasElement.prototype, {
    getContext: function() {
      var context = this.impl.getContext.apply(this.impl, arguments);
      return context && wrap(context);
    }
  });

  registerWrapper(OriginalHTMLCanvasElement, HTMLCanvasElement,
                  document.createElement('canvas'));

  scope.wrappers.HTMLCanvasElement = HTMLCanvasElement;
})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var HTMLElement = scope.wrappers.HTMLElement;
  var mixin = scope.mixin;
  var registerWrapper = scope.registerWrapper;

  var OriginalHTMLContentElement = window.HTMLContentElement;

  function HTMLContentElement(node) {
    HTMLElement.call(this, node);
  }
  HTMLContentElement.prototype = Object.create(HTMLElement.prototype);
  mixin(HTMLContentElement.prototype, {
    get select() {
      return this.getAttribute('select');
    },
    set select(value) {
      this.setAttribute('select', value);
    },

    setAttribute: function(n, v) {
      HTMLElement.prototype.setAttribute.call(this, n, v);
      if (String(n).toLowerCase() === 'select')
        this.invalidateShadowRenderer(true);
    }

    // getDistributedNodes is added in ShadowRenderer

    // TODO: attribute boolean resetStyleInheritance;
  });

  if (OriginalHTMLContentElement)
    registerWrapper(OriginalHTMLContentElement, HTMLContentElement);

  scope.wrappers.HTMLContentElement = HTMLContentElement;
})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var HTMLElement = scope.wrappers.HTMLElement;
  var registerWrapper = scope.registerWrapper;
  var unwrap = scope.unwrap;
  var rewrap = scope.rewrap;

  var OriginalHTMLImageElement = window.HTMLImageElement;

  function HTMLImageElement(node) {
    HTMLElement.call(this, node);
  }
  HTMLImageElement.prototype = Object.create(HTMLElement.prototype);

  registerWrapper(OriginalHTMLImageElement, HTMLImageElement,
                  document.createElement('img'));

  function Image(width, height) {
    if (!(this instanceof Image)) {
      throw new TypeError(
          'DOM object constructor cannot be called as a function.');
    }

    var node = unwrap(document.createElement('img'));
    HTMLElement.call(this, node);
    rewrap(node, this);

    if (width !== undefined)
      node.width = width;
    if (height !== undefined)
      node.height = height;
  }

  Image.prototype = HTMLImageElement.prototype;

  scope.wrappers.HTMLImageElement = HTMLImageElement;
  scope.wrappers.Image = Image;
})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var HTMLElement = scope.wrappers.HTMLElement;
  var mixin = scope.mixin;
  var registerWrapper = scope.registerWrapper;

  var OriginalHTMLShadowElement = window.HTMLShadowElement;

  function HTMLShadowElement(node) {
    HTMLElement.call(this, node);
  }
  HTMLShadowElement.prototype = Object.create(HTMLElement.prototype);
  mixin(HTMLShadowElement.prototype, {
    // TODO: attribute boolean resetStyleInheritance;
  });

  if (OriginalHTMLShadowElement)
    registerWrapper(OriginalHTMLShadowElement, HTMLShadowElement);

  scope.wrappers.HTMLShadowElement = HTMLShadowElement;
})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var HTMLElement = scope.wrappers.HTMLElement;
  var mixin = scope.mixin;
  var registerWrapper = scope.registerWrapper;
  var unwrap = scope.unwrap;
  var wrap = scope.wrap;

  var contentTable = new WeakMap();
  var templateContentsOwnerTable = new WeakMap();

  // http://dvcs.w3.org/hg/webcomponents/raw-file/tip/spec/templates/index.html#dfn-template-contents-owner
  function getTemplateContentsOwner(doc) {
    if (!doc.defaultView)
      return doc;
    var d = templateContentsOwnerTable.get(doc);
    if (!d) {
      // TODO(arv): This should either be a Document or HTMLDocument depending
      // on doc.
      d = doc.implementation.createHTMLDocument('');
      while (d.lastChild) {
        d.removeChild(d.lastChild);
      }
      templateContentsOwnerTable.set(doc, d);
    }
    return d;
  }

  function extractContent(templateElement) {
    // templateElement is not a wrapper here.
    var doc = getTemplateContentsOwner(templateElement.ownerDocument);
    var df = unwrap(doc.createDocumentFragment());
    var child;
    while (child = templateElement.firstChild) {
      df.appendChild(child);
    }
    return df;
  }

  var OriginalHTMLTemplateElement = window.HTMLTemplateElement;

  function HTMLTemplateElement(node) {
    HTMLElement.call(this, node);
    if (!OriginalHTMLTemplateElement) {
      var content = extractContent(node);
      contentTable.set(this, wrap(content));
    }
  }
  HTMLTemplateElement.prototype = Object.create(HTMLElement.prototype);

  mixin(HTMLTemplateElement.prototype, {
    get content() {
      if (OriginalHTMLTemplateElement)
        return wrap(this.impl.content);
      return contentTable.get(this);
    },

    // TODO(arv): cloneNode needs to clone content.

  });

  if (OriginalHTMLTemplateElement)
    registerWrapper(OriginalHTMLTemplateElement, HTMLTemplateElement);

  scope.wrappers.HTMLTemplateElement = HTMLTemplateElement;
})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var HTMLElement = scope.wrappers.HTMLElement;
  var registerWrapper = scope.registerWrapper;

  var OriginalHTMLMediaElement = window.HTMLMediaElement;

  function HTMLMediaElement(node) {
    HTMLElement.call(this, node);
  }
  HTMLMediaElement.prototype = Object.create(HTMLElement.prototype);

  registerWrapper(OriginalHTMLMediaElement, HTMLMediaElement,
                  document.createElement('audio'));

  scope.wrappers.HTMLMediaElement = HTMLMediaElement;
})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var HTMLMediaElement = scope.wrappers.HTMLMediaElement;
  var registerWrapper = scope.registerWrapper;
  var unwrap = scope.unwrap;
  var rewrap = scope.rewrap;

  var OriginalHTMLAudioElement = window.HTMLAudioElement;

  function HTMLAudioElement(node) {
    HTMLMediaElement.call(this, node);
  }
  HTMLAudioElement.prototype = Object.create(HTMLMediaElement.prototype);

  registerWrapper(OriginalHTMLAudioElement, HTMLAudioElement,
                  document.createElement('audio'));

  function Audio(src) {
    if (!(this instanceof Audio)) {
      throw new TypeError(
          'DOM object constructor cannot be called as a function.');
    }

    var node = unwrap(document.createElement('audio'));
    HTMLMediaElement.call(this, node);
    rewrap(node, this);

    node.setAttribute('preload', 'auto');
    if (src !== undefined)
      node.setAttribute('src', src);
  }

  Audio.prototype = HTMLAudioElement.prototype;

  scope.wrappers.HTMLAudioElement = HTMLAudioElement;
  scope.wrappers.Audio = Audio;
})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var HTMLElement = scope.wrappers.HTMLElement;
  var mixin = scope.mixin;
  var registerWrapper = scope.registerWrapper;
  var rewrap = scope.rewrap;
  var unwrap = scope.unwrap;
  var wrap = scope.wrap;

  var OriginalHTMLOptionElement = window.HTMLOptionElement;

  function trimText(s) {
    return s.replace(/\s+/g, ' ').trim();
  }

  function HTMLOptionElement(node) {
    HTMLElement.call(this, node);
  }
  HTMLOptionElement.prototype = Object.create(HTMLElement.prototype);
  mixin(HTMLOptionElement.prototype, {
    get text() {
      return trimText(this.textContent);
    },
    set text(value) {
      this.textContent = trimText(String(value));
    },
    get form() {
      return wrap(unwrap(this).form);
    }
  });

  registerWrapper(OriginalHTMLOptionElement, HTMLOptionElement,
                  document.createElement('option'));

  function Option(text, value, defaultSelected, selected) {
    if (!(this instanceof Option)) {
      throw new TypeError(
          'DOM object constructor cannot be called as a function.');
    }

    var node = unwrap(document.createElement('option'));
    HTMLElement.call(this, node);
    rewrap(node, this);

    if (text !== undefined)
      node.text = text;
    if (value !== undefined)
      node.setAttribute('value', value);
    if (defaultSelected === true)
      node.setAttribute('selected', '');
    node.selected = selected === true;
  }

  Option.prototype = HTMLOptionElement.prototype;

  scope.wrappers.HTMLOptionElement = HTMLOptionElement;
  scope.wrappers.Option = Option;
})(window.ShadowDOMPolyfill);

// Copyright 2014 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var HTMLElement = scope.wrappers.HTMLElement;
  var mixin = scope.mixin;
  var registerWrapper = scope.registerWrapper;
  var unwrap = scope.unwrap;
  var wrap = scope.wrap;

  var OriginalHTMLSelectElement = window.HTMLSelectElement;

  function HTMLSelectElement(node) {
    HTMLElement.call(this, node);
  }
  HTMLSelectElement.prototype = Object.create(HTMLElement.prototype);
  mixin(HTMLSelectElement.prototype, {
    add: function(element, before) {
      if (typeof before === 'object')  // also includes null
        before = unwrap(before);
      unwrap(this).add(unwrap(element), before);
    },

    remove: function(indexOrNode) {
      // Spec only allows index but implementations allow index or node.
      // remove() is also allowed which is same as remove(undefined)
      if (indexOrNode === undefined) {
        HTMLElement.prototype.remove.call(this);
        return;
      }

      if (typeof indexOrNode === 'object')
        indexOrNode = unwrap(indexOrNode);

      unwrap(this).remove(indexOrNode);
    },

    get form() {
      return wrap(unwrap(this).form);
    }
  });

  registerWrapper(OriginalHTMLSelectElement, HTMLSelectElement,
                  document.createElement('select'));

  scope.wrappers.HTMLSelectElement = HTMLSelectElement;
})(window.ShadowDOMPolyfill);

/*
 * Copyright 2014 The Polymer Authors. All rights reserved.
 * Use of this source code is goverened by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {
  'use strict';

  var HTMLElement = scope.wrappers.HTMLElement;
  var mixin = scope.mixin;
  var registerWrapper = scope.registerWrapper;
  var unwrap = scope.unwrap;
  var wrap = scope.wrap;
  var wrapHTMLCollection = scope.wrapHTMLCollection;

  var OriginalHTMLTableElement = window.HTMLTableElement;

  function HTMLTableElement(node) {
    HTMLElement.call(this, node);
  }
  HTMLTableElement.prototype = Object.create(HTMLElement.prototype);
  mixin(HTMLTableElement.prototype, {
    get caption() {
      return wrap(unwrap(this).caption);
    },
    createCaption: function() {
      return wrap(unwrap(this).createCaption());
    },

    get tHead() {
      return wrap(unwrap(this).tHead);
    },
    createTHead: function() {
      return wrap(unwrap(this).createTHead());
    },

    createTFoot: function() {
      return wrap(unwrap(this).createTFoot());
    },
    get tFoot() {
      return wrap(unwrap(this).tFoot);
    },

    get tBodies() {
      return wrapHTMLCollection(unwrap(this).tBodies);
    },
    createTBody: function() {
      return wrap(unwrap(this).createTBody());
    },

    get rows() {
      return wrapHTMLCollection(unwrap(this).rows);
    },
    insertRow: function(index) {
      return wrap(unwrap(this).insertRow(index));
    }
  });

  registerWrapper(OriginalHTMLTableElement, HTMLTableElement,
                  document.createElement('table'));

  scope.wrappers.HTMLTableElement = HTMLTableElement;
})(window.ShadowDOMPolyfill);

/*
 * Copyright 2014 The Polymer Authors. All rights reserved.
 * Use of this source code is goverened by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {
  'use strict';

  var HTMLElement = scope.wrappers.HTMLElement;
  var mixin = scope.mixin;
  var registerWrapper = scope.registerWrapper;
  var wrapHTMLCollection = scope.wrapHTMLCollection;
  var unwrap = scope.unwrap;
  var wrap = scope.wrap;

  var OriginalHTMLTableSectionElement = window.HTMLTableSectionElement;

  function HTMLTableSectionElement(node) {
    HTMLElement.call(this, node);
  }
  HTMLTableSectionElement.prototype = Object.create(HTMLElement.prototype);
  mixin(HTMLTableSectionElement.prototype, {
    get rows() {
      return wrapHTMLCollection(unwrap(this).rows);
    },
    insertRow: function(index) {
      return wrap(unwrap(this).insertRow(index));
    }
  });

  registerWrapper(OriginalHTMLTableSectionElement, HTMLTableSectionElement,
                  document.createElement('thead'));

  scope.wrappers.HTMLTableSectionElement = HTMLTableSectionElement;
})(window.ShadowDOMPolyfill);

/*
 * Copyright 2014 The Polymer Authors. All rights reserved.
 * Use of this source code is goverened by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {
  'use strict';

  var HTMLElement = scope.wrappers.HTMLElement;
  var mixin = scope.mixin;
  var registerWrapper = scope.registerWrapper;
  var wrapHTMLCollection = scope.wrapHTMLCollection;
  var unwrap = scope.unwrap;
  var wrap = scope.wrap;

  var OriginalHTMLTableRowElement = window.HTMLTableRowElement;

  function HTMLTableRowElement(node) {
    HTMLElement.call(this, node);
  }
  HTMLTableRowElement.prototype = Object.create(HTMLElement.prototype);
  mixin(HTMLTableRowElement.prototype, {
    get cells() {
      return wrapHTMLCollection(unwrap(this).cells);
    },

    insertCell: function(index) {
      return wrap(unwrap(this).insertCell(index));
    }
  });

  registerWrapper(OriginalHTMLTableRowElement, HTMLTableRowElement,
                  document.createElement('tr'));

  scope.wrappers.HTMLTableRowElement = HTMLTableRowElement;
})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var HTMLContentElement = scope.wrappers.HTMLContentElement;
  var HTMLElement = scope.wrappers.HTMLElement;
  var HTMLShadowElement = scope.wrappers.HTMLShadowElement;
  var HTMLTemplateElement = scope.wrappers.HTMLTemplateElement;
  var mixin = scope.mixin;
  var registerWrapper = scope.registerWrapper;

  var OriginalHTMLUnknownElement = window.HTMLUnknownElement;

  function HTMLUnknownElement(node) {
    switch (node.localName) {
      case 'content':
        return new HTMLContentElement(node);
      case 'shadow':
        return new HTMLShadowElement(node);
      case 'template':
        return new HTMLTemplateElement(node);
    }
    HTMLElement.call(this, node);
  }
  HTMLUnknownElement.prototype = Object.create(HTMLElement.prototype);
  registerWrapper(OriginalHTMLUnknownElement, HTMLUnknownElement);
  scope.wrappers.HTMLUnknownElement = HTMLUnknownElement;
})(window.ShadowDOMPolyfill);

// Copyright 2014 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var registerObject = scope.registerObject;

  var SVG_NS = 'http://www.w3.org/2000/svg';
  var svgTitleElement = document.createElementNS(SVG_NS, 'title');
  var SVGTitleElement = registerObject(svgTitleElement);
  var SVGElement = Object.getPrototypeOf(SVGTitleElement.prototype).constructor;

  scope.wrappers.SVGElement = SVGElement;
})(window.ShadowDOMPolyfill);

// Copyright 2014 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var mixin = scope.mixin;
  var registerWrapper = scope.registerWrapper;
  var unwrap = scope.unwrap;
  var wrap = scope.wrap;

  var OriginalSVGUseElement = window.SVGUseElement;

  // IE uses SVGElement as parent interface, SVG2 (Blink & Gecko) uses
  // SVGGraphicsElement. Use the <g> element to get the right prototype.

  var SVG_NS = 'http://www.w3.org/2000/svg';
  var gWrapper = wrap(document.createElementNS(SVG_NS, 'g'));
  var useElement = document.createElementNS(SVG_NS, 'use');
  var SVGGElement = gWrapper.constructor;
  var parentInterfacePrototype = Object.getPrototypeOf(SVGGElement.prototype);
  var parentInterface = parentInterfacePrototype.constructor;

  function SVGUseElement(impl) {
    parentInterface.call(this, impl);
  }

  SVGUseElement.prototype = Object.create(parentInterfacePrototype);

  // Firefox does not expose instanceRoot.
  if ('instanceRoot' in useElement) {
    mixin(SVGUseElement.prototype, {
      get instanceRoot() {
        return wrap(unwrap(this).instanceRoot);
      },
      get animatedInstanceRoot() {
        return wrap(unwrap(this).animatedInstanceRoot);
      },
    });
  }

  registerWrapper(OriginalSVGUseElement, SVGUseElement, useElement);

  scope.wrappers.SVGUseElement = SVGUseElement;
})(window.ShadowDOMPolyfill);

// Copyright 2014 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var EventTarget = scope.wrappers.EventTarget;
  var mixin = scope.mixin;
  var registerWrapper = scope.registerWrapper;
  var wrap = scope.wrap;

  var OriginalSVGElementInstance = window.SVGElementInstance;
  if (!OriginalSVGElementInstance)
    return;

  function SVGElementInstance(impl) {
    EventTarget.call(this, impl);
  }

  SVGElementInstance.prototype = Object.create(EventTarget.prototype);
  mixin(SVGElementInstance.prototype, {
    /** @type {SVGElement} */
    get correspondingElement() {
      return wrap(this.impl.correspondingElement);
    },

    /** @type {SVGUseElement} */
    get correspondingUseElement() {
      return wrap(this.impl.correspondingUseElement);
    },

    /** @type {SVGElementInstance} */
    get parentNode() {
      return wrap(this.impl.parentNode);
    },

    /** @type {SVGElementInstanceList} */
    get childNodes() {
      throw new Error('Not implemented');
    },

    /** @type {SVGElementInstance} */
    get firstChild() {
      return wrap(this.impl.firstChild);
    },

    /** @type {SVGElementInstance} */
    get lastChild() {
      return wrap(this.impl.lastChild);
    },

    /** @type {SVGElementInstance} */
    get previousSibling() {
      return wrap(this.impl.previousSibling);
    },

    /** @type {SVGElementInstance} */
    get nextSibling() {
      return wrap(this.impl.nextSibling);
    }
  });

  registerWrapper(OriginalSVGElementInstance, SVGElementInstance);

  scope.wrappers.SVGElementInstance = SVGElementInstance;
})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var mixin = scope.mixin;
  var registerWrapper = scope.registerWrapper;
  var unwrap = scope.unwrap;
  var unwrapIfNeeded = scope.unwrapIfNeeded;
  var wrap = scope.wrap;

  var OriginalCanvasRenderingContext2D = window.CanvasRenderingContext2D;

  function CanvasRenderingContext2D(impl) {
    this.impl = impl;
  }

  mixin(CanvasRenderingContext2D.prototype, {
    get canvas() {
      return wrap(this.impl.canvas);
    },

    drawImage: function() {
      arguments[0] = unwrapIfNeeded(arguments[0]);
      this.impl.drawImage.apply(this.impl, arguments);
    },

    createPattern: function() {
      arguments[0] = unwrap(arguments[0]);
      return this.impl.createPattern.apply(this.impl, arguments);
    }
  });

  registerWrapper(OriginalCanvasRenderingContext2D, CanvasRenderingContext2D,
                  document.createElement('canvas').getContext('2d'));

  scope.wrappers.CanvasRenderingContext2D = CanvasRenderingContext2D;
})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var mixin = scope.mixin;
  var registerWrapper = scope.registerWrapper;
  var unwrapIfNeeded = scope.unwrapIfNeeded;
  var wrap = scope.wrap;

  var OriginalWebGLRenderingContext = window.WebGLRenderingContext;

  // IE10 does not have WebGL.
  if (!OriginalWebGLRenderingContext)
    return;

  function WebGLRenderingContext(impl) {
    this.impl = impl;
  }

  mixin(WebGLRenderingContext.prototype, {
    get canvas() {
      return wrap(this.impl.canvas);
    },

    texImage2D: function() {
      arguments[5] = unwrapIfNeeded(arguments[5]);
      this.impl.texImage2D.apply(this.impl, arguments);
    },

    texSubImage2D: function() {
      arguments[6] = unwrapIfNeeded(arguments[6]);
      this.impl.texSubImage2D.apply(this.impl, arguments);
    }
  });

  // Blink/WebKit has broken DOM bindings. Usually we would create an instance
  // of the object and pass it into registerWrapper as a "blueprint" but
  // creating WebGL contexts is expensive and might fail so we use a dummy
  // object with dummy instance properties for these broken browsers.
  var instanceProperties = /WebKit/.test(navigator.userAgent) ?
      {drawingBufferHeight: null, drawingBufferWidth: null} : {};

  registerWrapper(OriginalWebGLRenderingContext, WebGLRenderingContext,
      instanceProperties);

  scope.wrappers.WebGLRenderingContext = WebGLRenderingContext;
})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var registerWrapper = scope.registerWrapper;
  var unwrap = scope.unwrap;
  var unwrapIfNeeded = scope.unwrapIfNeeded;
  var wrap = scope.wrap;

  var OriginalRange = window.Range;

  function Range(impl) {
    this.impl = impl;
  }
  Range.prototype = {
    get startContainer() {
      return wrap(this.impl.startContainer);
    },
    get endContainer() {
      return wrap(this.impl.endContainer);
    },
    get commonAncestorContainer() {
      return wrap(this.impl.commonAncestorContainer);
    },
    setStart: function(refNode,offset) {
      this.impl.setStart(unwrapIfNeeded(refNode), offset);
    },
    setEnd: function(refNode,offset) {
      this.impl.setEnd(unwrapIfNeeded(refNode), offset);
    },
    setStartBefore: function(refNode) {
      this.impl.setStartBefore(unwrapIfNeeded(refNode));
    },
    setStartAfter: function(refNode) {
      this.impl.setStartAfter(unwrapIfNeeded(refNode));
    },
    setEndBefore: function(refNode) {
      this.impl.setEndBefore(unwrapIfNeeded(refNode));
    },
    setEndAfter: function(refNode) {
      this.impl.setEndAfter(unwrapIfNeeded(refNode));
    },
    selectNode: function(refNode) {
      this.impl.selectNode(unwrapIfNeeded(refNode));
    },
    selectNodeContents: function(refNode) {
      this.impl.selectNodeContents(unwrapIfNeeded(refNode));
    },
    compareBoundaryPoints: function(how, sourceRange) {
      return this.impl.compareBoundaryPoints(how, unwrap(sourceRange));
    },
    extractContents: function() {
      return wrap(this.impl.extractContents());
    },
    cloneContents: function() {
      return wrap(this.impl.cloneContents());
    },
    insertNode: function(node) {
      this.impl.insertNode(unwrapIfNeeded(node));
    },
    surroundContents: function(newParent) {
      this.impl.surroundContents(unwrapIfNeeded(newParent));
    },
    cloneRange: function() {
      return wrap(this.impl.cloneRange());
    },
    isPointInRange: function(node, offset) {
      return this.impl.isPointInRange(unwrapIfNeeded(node), offset);
    },
    comparePoint: function(node, offset) {
      return this.impl.comparePoint(unwrapIfNeeded(node), offset);
    },
    intersectsNode: function(node) {
      return this.impl.intersectsNode(unwrapIfNeeded(node));
    },
    toString: function() {
      return this.impl.toString();
    }
  };

  // IE9 does not have createContextualFragment.
  if (OriginalRange.prototype.createContextualFragment) {
    Range.prototype.createContextualFragment = function(html) {
      return wrap(this.impl.createContextualFragment(html));
    };
  }

  registerWrapper(window.Range, Range, document.createRange());

  scope.wrappers.Range = Range;

})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var GetElementsByInterface = scope.GetElementsByInterface;
  var ParentNodeInterface = scope.ParentNodeInterface;
  var SelectorsInterface = scope.SelectorsInterface;
  var mixin = scope.mixin;
  var registerObject = scope.registerObject;

  var DocumentFragment = registerObject(document.createDocumentFragment());
  mixin(DocumentFragment.prototype, ParentNodeInterface);
  mixin(DocumentFragment.prototype, SelectorsInterface);
  mixin(DocumentFragment.prototype, GetElementsByInterface);

  var Comment = registerObject(document.createComment(''));

  scope.wrappers.Comment = Comment;
  scope.wrappers.DocumentFragment = DocumentFragment;

})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var DocumentFragment = scope.wrappers.DocumentFragment;
  var TreeScope = scope.TreeScope;
  var elementFromPoint = scope.elementFromPoint;
  var getInnerHTML = scope.getInnerHTML;
  var getTreeScope = scope.getTreeScope;
  var mixin = scope.mixin;
  var rewrap = scope.rewrap;
  var setInnerHTML = scope.setInnerHTML;
  var unwrap = scope.unwrap;

  var shadowHostTable = new WeakMap();
  var nextOlderShadowTreeTable = new WeakMap();

  var spaceCharRe = /[ \t\n\r\f]/;

  function ShadowRoot(hostWrapper) {
    var node = unwrap(hostWrapper.impl.ownerDocument.createDocumentFragment());
    DocumentFragment.call(this, node);

    // createDocumentFragment associates the node with a wrapper
    // DocumentFragment instance. Override that.
    rewrap(node, this);

    this.treeScope_ = new TreeScope(this, getTreeScope(hostWrapper));

    var oldShadowRoot = hostWrapper.shadowRoot;
    nextOlderShadowTreeTable.set(this, oldShadowRoot);

    shadowHostTable.set(this, hostWrapper);
  }
  ShadowRoot.prototype = Object.create(DocumentFragment.prototype);
  mixin(ShadowRoot.prototype, {
    get innerHTML() {
      return getInnerHTML(this);
    },
    set innerHTML(value) {
      setInnerHTML(this, value);
      this.invalidateShadowRenderer();
    },

    get olderShadowRoot() {
      return nextOlderShadowTreeTable.get(this) || null;
    },

    get host() {
      return shadowHostTable.get(this) || null;
    },

    invalidateShadowRenderer: function() {
      return shadowHostTable.get(this).invalidateShadowRenderer();
    },

    elementFromPoint: function(x, y) {
      return elementFromPoint(this, this.ownerDocument, x, y);
    },

    getElementById: function(id) {
      if (spaceCharRe.test(id))
        return null;
      return this.querySelector('[id="' + id + '"]');
    }
  });

  scope.wrappers.ShadowRoot = ShadowRoot;

})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var Element = scope.wrappers.Element;
  var HTMLContentElement = scope.wrappers.HTMLContentElement;
  var HTMLShadowElement = scope.wrappers.HTMLShadowElement;
  var Node = scope.wrappers.Node;
  var ShadowRoot = scope.wrappers.ShadowRoot;
  var assert = scope.assert;
  var getTreeScope = scope.getTreeScope;
  var mixin = scope.mixin;
  var oneOf = scope.oneOf;
  var unwrap = scope.unwrap;
  var wrap = scope.wrap;

  /**
   * Updates the fields of a wrapper to a snapshot of the logical DOM as needed.
   * Up means parentNode
   * Sideways means previous and next sibling.
   * @param {!Node} wrapper
   */
  function updateWrapperUpAndSideways(wrapper) {
    wrapper.previousSibling_ = wrapper.previousSibling;
    wrapper.nextSibling_ = wrapper.nextSibling;
    wrapper.parentNode_ = wrapper.parentNode;
  }

  /**
   * Updates the fields of a wrapper to a snapshot of the logical DOM as needed.
   * Down means first and last child
   * @param {!Node} wrapper
   */
  function updateWrapperDown(wrapper) {
    wrapper.firstChild_ = wrapper.firstChild;
    wrapper.lastChild_ = wrapper.lastChild;
  }

  function updateAllChildNodes(parentNodeWrapper) {
    assert(parentNodeWrapper instanceof Node);
    for (var childWrapper = parentNodeWrapper.firstChild;
         childWrapper;
         childWrapper = childWrapper.nextSibling) {
      updateWrapperUpAndSideways(childWrapper);
    }
    updateWrapperDown(parentNodeWrapper);
  }

  function insertBefore(parentNodeWrapper, newChildWrapper, refChildWrapper) {
    var parentNode = unwrap(parentNodeWrapper);
    var newChild = unwrap(newChildWrapper);
    var refChild = refChildWrapper ? unwrap(refChildWrapper) : null;

    remove(newChildWrapper);
    updateWrapperUpAndSideways(newChildWrapper);

    if (!refChildWrapper) {
      parentNodeWrapper.lastChild_ = parentNodeWrapper.lastChild;
      if (parentNodeWrapper.lastChild === parentNodeWrapper.firstChild)
        parentNodeWrapper.firstChild_ = parentNodeWrapper.firstChild;

      var lastChildWrapper = wrap(parentNode.lastChild);
      if (lastChildWrapper)
        lastChildWrapper.nextSibling_ = lastChildWrapper.nextSibling;
    } else {
      if (parentNodeWrapper.firstChild === refChildWrapper)
        parentNodeWrapper.firstChild_ = refChildWrapper;

      refChildWrapper.previousSibling_ = refChildWrapper.previousSibling;
    }

    parentNode.insertBefore(newChild, refChild);
  }

  function remove(nodeWrapper) {
    var node = unwrap(nodeWrapper)
    var parentNode = node.parentNode;
    if (!parentNode)
      return;

    var parentNodeWrapper = wrap(parentNode);
    updateWrapperUpAndSideways(nodeWrapper);

    if (nodeWrapper.previousSibling)
      nodeWrapper.previousSibling.nextSibling_ = nodeWrapper;
    if (nodeWrapper.nextSibling)
      nodeWrapper.nextSibling.previousSibling_ = nodeWrapper;

    if (parentNodeWrapper.lastChild === nodeWrapper)
      parentNodeWrapper.lastChild_ = nodeWrapper;
    if (parentNodeWrapper.firstChild === nodeWrapper)
      parentNodeWrapper.firstChild_ = nodeWrapper;

    parentNode.removeChild(node);
  }

  var distributedChildNodesTable = new WeakMap();
  var eventParentsTable = new WeakMap();
  var insertionParentTable = new WeakMap();
  var rendererForHostTable = new WeakMap();

  function distributeChildToInsertionPoint(child, insertionPoint) {
    getDistributedChildNodes(insertionPoint).push(child);
    assignToInsertionPoint(child, insertionPoint);

    var eventParents = eventParentsTable.get(child);
    if (!eventParents)
      eventParentsTable.set(child, eventParents = []);
    eventParents.push(insertionPoint);
  }

  function resetDistributedChildNodes(insertionPoint) {
    distributedChildNodesTable.set(insertionPoint, []);
  }

  function getDistributedChildNodes(insertionPoint) {
    var rv = distributedChildNodesTable.get(insertionPoint);
    if (!rv)
      distributedChildNodesTable.set(insertionPoint, rv = []);
    return rv;
  }

  function getChildNodesSnapshot(node) {
    var result = [], i = 0;
    for (var child = node.firstChild; child; child = child.nextSibling) {
      result[i++] = child;
    }
    return result;
  }

  /**
   * Visits all nodes in the tree that fulfils the |predicate|. If the |visitor|
   * function returns |false| the traversal is aborted.
   * @param {!Node} tree
   * @param {function(!Node) : boolean} predicate
   * @param {function(!Node) : *} visitor
   */
  function visit(tree, predicate, visitor) {
    // This operates on logical DOM.
    for (var node = tree.firstChild; node; node = node.nextSibling) {
      if (predicate(node)) {
        if (visitor(node) === false)
          return;
      } else {
        visit(node, predicate, visitor);
      }
    }
  }

  // Matching Insertion Points
  // http://dvcs.w3.org/hg/webcomponents/raw-file/tip/spec/shadow/index.html#matching-insertion-points

  // TODO(arv): Verify this... I don't remember why I picked this regexp.
  var selectorMatchRegExp = /^[*.:#[a-zA-Z_|]/;

  var allowedPseudoRegExp = new RegExp('^:(' + [
    'link',
    'visited',
    'target',
    'enabled',
    'disabled',
    'checked',
    'indeterminate',
    'nth-child',
    'nth-last-child',
    'nth-of-type',
    'nth-last-of-type',
    'first-child',
    'last-child',
    'first-of-type',
    'last-of-type',
    'only-of-type',
  ].join('|') + ')');


  /**
   * @param {Element} node
   * @oaram {Element} point The insertion point element.
   * @return {boolean} Whether the node matches the insertion point.
   */
  function matchesCriteria(node, point) {
    var select = point.getAttribute('select');
    if (!select)
      return true;

    // Here we know the select attribute is a non empty string.
    select = select.trim();
    if (!select)
      return true;

    if (!(node instanceof Element))
      return false;

    // The native matches function in IE9 does not correctly work with elements
    // that are not in the document.
    // TODO(arv): Implement matching in JS.
    // https://github.com/Polymer/ShadowDOM/issues/361
    if (select === '*' || select === node.localName)
      return true;

    // TODO(arv): This does not seem right. Need to check for a simple selector.
    if (!selectorMatchRegExp.test(select))
      return false;

    // TODO(arv): This no longer matches the spec.
    if (select[0] === ':' && !allowedPseudoRegExp.test(select))
      return false;

    try {
      return node.matches(select);
    } catch (ex) {
      // Invalid selector.
      return false;
    }
  }

  var request = oneOf(window, [
    'requestAnimationFrame',
    'mozRequestAnimationFrame',
    'webkitRequestAnimationFrame',
    'setTimeout'
  ]);

  var pendingDirtyRenderers = [];
  var renderTimer;

  function renderAllPending() {
    // TODO(arv): Order these in document order. That way we do not have to
    // render something twice.
    for (var i = 0; i < pendingDirtyRenderers.length; i++) {
      var renderer = pendingDirtyRenderers[i];
      var parentRenderer = renderer.parentRenderer;
      if (parentRenderer && parentRenderer.dirty)
        continue;
      renderer.render();
    }

    pendingDirtyRenderers = [];
  }

  function handleRequestAnimationFrame() {
    renderTimer = null;
    renderAllPending();
  }

  /**
   * Returns existing shadow renderer for a host or creates it if it is needed.
   * @params {!Element} host
   * @return {!ShadowRenderer}
   */
  function getRendererForHost(host) {
    var renderer = rendererForHostTable.get(host);
    if (!renderer) {
      renderer = new ShadowRenderer(host);
      rendererForHostTable.set(host, renderer);
    }
    return renderer;
  }

  function getShadowRootAncestor(node) {
    var root = getTreeScope(node).root;
    if (root instanceof ShadowRoot)
      return root;
    return null;
  }

  function getRendererForShadowRoot(shadowRoot) {
    return getRendererForHost(shadowRoot.host);
  }

  var spliceDiff = new ArraySplice();
  spliceDiff.equals = function(renderNode, rawNode) {
    return unwrap(renderNode.node) === rawNode;
  };

  /**
   * RenderNode is used as an in memory "render tree". When we render the
   * composed tree we create a tree of RenderNodes, then we diff this against
   * the real DOM tree and make minimal changes as needed.
   */
  function RenderNode(node) {
    this.skip = false;
    this.node = node;
    this.childNodes = [];
  }

  RenderNode.prototype = {
    append: function(node) {
      var rv = new RenderNode(node);
      this.childNodes.push(rv);
      return rv;
    },

    sync: function(opt_added) {
      if (this.skip)
        return;

      var nodeWrapper = this.node;
      // plain array of RenderNodes
      var newChildren = this.childNodes;
      // plain array of real nodes.
      var oldChildren = getChildNodesSnapshot(unwrap(nodeWrapper));
      var added = opt_added || new WeakMap();

      var splices = spliceDiff.calculateSplices(newChildren, oldChildren);

      var newIndex = 0, oldIndex = 0;
      var lastIndex = 0;
      for (var i = 0; i < splices.length; i++) {
        var splice = splices[i];
        for (; lastIndex < splice.index; lastIndex++) {
          oldIndex++;
          newChildren[newIndex++].sync(added);
        }

        var removedCount = splice.removed.length;
        for (var j = 0; j < removedCount; j++) {
          var wrapper = wrap(oldChildren[oldIndex++]);
          if (!added.get(wrapper))
            remove(wrapper);
        }

        var addedCount = splice.addedCount;
        var refNode = oldChildren[oldIndex] && wrap(oldChildren[oldIndex]);
        for (var j = 0; j < addedCount; j++) {
          var newChildRenderNode = newChildren[newIndex++];
          var newChildWrapper = newChildRenderNode.node;
          insertBefore(nodeWrapper, newChildWrapper, refNode);

          // Keep track of added so that we do not remove the node after it
          // has been added.
          added.set(newChildWrapper, true);

          newChildRenderNode.sync(added);
        }

        lastIndex += addedCount;
      }

      for (var i = lastIndex; i < newChildren.length; i++) {
        newChildren[i].sync(added);
      }
    }
  };

  function ShadowRenderer(host) {
    this.host = host;
    this.dirty = false;
    this.invalidateAttributes();
    this.associateNode(host);
  }

  ShadowRenderer.prototype = {

    // http://dvcs.w3.org/hg/webcomponents/raw-file/tip/spec/shadow/index.html#rendering-shadow-trees
    render: function(opt_renderNode) {
      if (!this.dirty)
        return;

      this.invalidateAttributes();
      this.treeComposition();

      var host = this.host;
      var shadowRoot = host.shadowRoot;

      this.associateNode(host);
      var topMostRenderer = !renderNode;
      var renderNode = opt_renderNode || new RenderNode(host);

      for (var node = shadowRoot.firstChild; node; node = node.nextSibling) {
        this.renderNode(shadowRoot, renderNode, node, false);
      }

      if (topMostRenderer)
        renderNode.sync();

      this.dirty = false;
    },

    get parentRenderer() {
      return getTreeScope(this.host).renderer;
    },

    invalidate: function() {
      if (!this.dirty) {
        this.dirty = true;
        pendingDirtyRenderers.push(this);
        if (renderTimer)
          return;
        renderTimer = window[request](handleRequestAnimationFrame, 0);
      }
    },

    renderNode: function(shadowRoot, renderNode, node, isNested) {
      if (isShadowHost(node)) {
        renderNode = renderNode.append(node);
        var renderer = getRendererForHost(node);
        renderer.dirty = true;  // Need to rerender due to reprojection.
        renderer.render(renderNode);
      } else if (isInsertionPoint(node)) {
        this.renderInsertionPoint(shadowRoot, renderNode, node, isNested);
      } else if (isShadowInsertionPoint(node)) {
        this.renderShadowInsertionPoint(shadowRoot, renderNode, node);
      } else {
        this.renderAsAnyDomTree(shadowRoot, renderNode, node, isNested);
      }
    },

    renderAsAnyDomTree: function(shadowRoot, renderNode, node, isNested) {
      renderNode = renderNode.append(node);

      if (isShadowHost(node)) {
        var renderer = getRendererForHost(node);
        renderNode.skip = !renderer.dirty;
        renderer.render(renderNode);
      } else {
        for (var child = node.firstChild; child; child = child.nextSibling) {
          this.renderNode(shadowRoot, renderNode, child, isNested);
        }
      }
    },

    renderInsertionPoint: function(shadowRoot, renderNode, insertionPoint,
                                   isNested) {
      var distributedChildNodes = getDistributedChildNodes(insertionPoint);
      if (distributedChildNodes.length) {
        this.associateNode(insertionPoint);

        for (var i = 0; i < distributedChildNodes.length; i++) {
          var child = distributedChildNodes[i];
          if (isInsertionPoint(child) && isNested)
            this.renderInsertionPoint(shadowRoot, renderNode, child, isNested);
          else
            this.renderAsAnyDomTree(shadowRoot, renderNode, child, isNested);
        }
      } else {
        this.renderFallbackContent(shadowRoot, renderNode, insertionPoint);
      }
      this.associateNode(insertionPoint.parentNode);
    },

    renderShadowInsertionPoint: function(shadowRoot, renderNode,
                                         shadowInsertionPoint) {
      var nextOlderTree = shadowRoot.olderShadowRoot;
      if (nextOlderTree) {
        assignToInsertionPoint(nextOlderTree, shadowInsertionPoint);
        this.associateNode(shadowInsertionPoint.parentNode);
        for (var node = nextOlderTree.firstChild;
             node;
             node = node.nextSibling) {
          this.renderNode(nextOlderTree, renderNode, node, true);
        }
      } else {
        this.renderFallbackContent(shadowRoot, renderNode,
                                   shadowInsertionPoint);
      }
    },

    renderFallbackContent: function(shadowRoot, renderNode, fallbackHost) {
      this.associateNode(fallbackHost);
      this.associateNode(fallbackHost.parentNode);
      for (var node = fallbackHost.firstChild; node; node = node.nextSibling) {
        this.renderAsAnyDomTree(shadowRoot, renderNode, node, false);
      }
    },

    /**
     * Invalidates the attributes used to keep track of which attributes may
     * cause the renderer to be invalidated.
     */
    invalidateAttributes: function() {
      this.attributes = Object.create(null);
    },

    /**
     * Parses the selector and makes this renderer dependent on the attribute
     * being used in the selector.
     * @param {string} selector
     */
    updateDependentAttributes: function(selector) {
      if (!selector)
        return;

      var attributes = this.attributes;

      // .class
      if (/\.\w+/.test(selector))
        attributes['class'] = true;

      // #id
      if (/#\w+/.test(selector))
        attributes['id'] = true;

      selector.replace(/\[\s*([^\s=\|~\]]+)/g, function(_, name) {
        attributes[name] = true;
      });

      // Pseudo selectors have been removed from the spec.
    },

    dependsOnAttribute: function(name) {
      return this.attributes[name];
    },

    // http://dvcs.w3.org/hg/webcomponents/raw-file/tip/spec/shadow/index.html#dfn-distribution-algorithm
    distribute: function(tree, pool) {
      var self = this;

      visit(tree, isActiveInsertionPoint,
          function(insertionPoint) {
            resetDistributedChildNodes(insertionPoint);
            self.updateDependentAttributes(
                insertionPoint.getAttribute('select'));

            for (var i = 0; i < pool.length; i++) {  // 1.2
              var node = pool[i];  // 1.2.1
              if (node === undefined)  // removed
                continue;
              if (matchesCriteria(node, insertionPoint)) {  // 1.2.2
                distributeChildToInsertionPoint(node, insertionPoint);  // 1.2.2.1
                pool[i] = undefined;  // 1.2.2.2
              }
            }
          });
    },

    // http://dvcs.w3.org/hg/webcomponents/raw-file/tip/spec/shadow/index.html#dfn-tree-composition
    treeComposition: function () {
      var shadowHost = this.host;
      var tree = shadowHost.shadowRoot;  // 1.
      var pool = [];  // 2.

      for (var child = shadowHost.firstChild;
           child;
           child = child.nextSibling) {  // 3.
        if (isInsertionPoint(child)) {  // 3.2.
          var reprojected = getDistributedChildNodes(child);  // 3.2.1.
          // if reprojected is undef... reset it?
          if (!reprojected || !reprojected.length)  // 3.2.2.
            reprojected = getChildNodesSnapshot(child);
          pool.push.apply(pool, reprojected);  // 3.2.3.
        } else {
          pool.push(child); // 3.3.
        }
      }

      var shadowInsertionPoint, point;
      while (tree) {  // 4.
        // 4.1.
        shadowInsertionPoint = undefined;  // Reset every iteration.
        visit(tree, isActiveShadowInsertionPoint, function(point) {
          shadowInsertionPoint = point;
          return false;
        });
        point = shadowInsertionPoint;

        this.distribute(tree, pool);  // 4.2.
        if (point) {  // 4.3.
          var nextOlderTree = tree.olderShadowRoot;  // 4.3.1.
          if (!nextOlderTree) {
            break;  // 4.3.1.1.
          } else {
            tree = nextOlderTree;  // 4.3.2.2.
            assignToInsertionPoint(tree, point);  // 4.3.2.2.
            continue;  // 4.3.2.3.
          }
        } else {
          break;  // 4.4.
        }
      }
    },

    associateNode: function(node) {
      node.impl.polymerShadowRenderer_ = this;
    }
  };

  function isInsertionPoint(node) {
    // Should this include <shadow>?
    return node instanceof HTMLContentElement;
  }

  function isActiveInsertionPoint(node) {
    // <content> inside another <content> or <shadow> is considered inactive.
    return node instanceof HTMLContentElement;
  }

  function isShadowInsertionPoint(node) {
    return node instanceof HTMLShadowElement;
  }

  function isActiveShadowInsertionPoint(node) {
    // <shadow> inside another <content> or <shadow> is considered inactive.
    return node instanceof HTMLShadowElement;
  }

  function isShadowHost(shadowHost) {
    return shadowHost.shadowRoot;
  }

  function getShadowTrees(host) {
    var trees = [];

    for (var tree = host.shadowRoot; tree; tree = tree.olderShadowRoot) {
      trees.push(tree);
    }
    return trees;
  }

  function assignToInsertionPoint(tree, point) {
    insertionParentTable.set(tree, point);
  }

  // http://dvcs.w3.org/hg/webcomponents/raw-file/tip/spec/shadow/index.html#rendering-shadow-trees
  function render(host) {
    new ShadowRenderer(host).render();
  };

  // Need to rerender shadow host when:
  //
  // - a direct child to the ShadowRoot is added or removed
  // - a direct child to the host is added or removed
  // - a new shadow root is created
  // - a direct child to a content/shadow element is added or removed
  // - a sibling to a content/shadow element is added or removed
  // - content[select] is changed
  // - an attribute in a direct child to a host is modified

  /**
   * This gets called when a node was added or removed to it.
   */
  Node.prototype.invalidateShadowRenderer = function(force) {
    var renderer = this.impl.polymerShadowRenderer_;
    if (renderer) {
      renderer.invalidate();
      return true;
    }

    return false;
  };

  HTMLContentElement.prototype.getDistributedNodes = function() {
    // TODO(arv): We should only rerender the dirty ancestor renderers (from
    // the root and down).
    renderAllPending();
    return getDistributedChildNodes(this);
  };

  HTMLShadowElement.prototype.nodeIsInserted_ =
  HTMLContentElement.prototype.nodeIsInserted_ = function() {
    // Invalidate old renderer if any.
    this.invalidateShadowRenderer();

    var shadowRoot = getShadowRootAncestor(this);
    var renderer;
    if (shadowRoot)
      renderer = getRendererForShadowRoot(shadowRoot);
    this.impl.polymerShadowRenderer_ = renderer;
    if (renderer)
      renderer.invalidate();
  };

  scope.eventParentsTable = eventParentsTable;
  scope.getRendererForHost = getRendererForHost;
  scope.getShadowTrees = getShadowTrees;
  scope.insertionParentTable = insertionParentTable;
  scope.renderAllPending = renderAllPending;

  // Exposed for testing
  scope.visual = {
    insertBefore: insertBefore,
    remove: remove,
  };

})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var HTMLElement = scope.wrappers.HTMLElement;
  var assert = scope.assert;
  var mixin = scope.mixin;
  var registerWrapper = scope.registerWrapper;
  var unwrap = scope.unwrap;
  var wrap = scope.wrap;

  var elementsWithFormProperty = [
    'HTMLButtonElement',
    'HTMLFieldSetElement',
    'HTMLInputElement',
    'HTMLKeygenElement',
    'HTMLLabelElement',
    'HTMLLegendElement',
    'HTMLObjectElement',
    // HTMLOptionElement is handled in HTMLOptionElement.js
    'HTMLOutputElement',
    // HTMLSelectElement is handled in HTMLSelectElement.js
    'HTMLTextAreaElement',
  ];

  function createWrapperConstructor(name) {
    if (!window[name])
      return;

    // Ensure we are not overriding an already existing constructor.
    assert(!scope.wrappers[name]);

    var GeneratedWrapper = function(node) {
      // At this point all of them extend HTMLElement.
      HTMLElement.call(this, node);
    }
    GeneratedWrapper.prototype = Object.create(HTMLElement.prototype);
    mixin(GeneratedWrapper.prototype, {
      get form() {
        return wrap(unwrap(this).form);
      },
    });

    registerWrapper(window[name], GeneratedWrapper,
        document.createElement(name.slice(4, -7)));
    scope.wrappers[name] = GeneratedWrapper;
  }

  elementsWithFormProperty.forEach(createWrapperConstructor);

})(window.ShadowDOMPolyfill);

// Copyright 2014 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var registerWrapper = scope.registerWrapper;
  var unwrap = scope.unwrap;
  var unwrapIfNeeded = scope.unwrapIfNeeded;
  var wrap = scope.wrap;

  var OriginalSelection = window.Selection;

  function Selection(impl) {
    this.impl = impl;
  }
  Selection.prototype = {
    get anchorNode() {
      return wrap(this.impl.anchorNode);
    },
    get focusNode() {
      return wrap(this.impl.focusNode);
    },
    addRange: function(range) {
      this.impl.addRange(unwrap(range));
    },
    collapse: function(node, index) {
      this.impl.collapse(unwrapIfNeeded(node), index);
    },
    containsNode: function(node, allowPartial) {
      return this.impl.containsNode(unwrapIfNeeded(node), allowPartial);
    },
    extend: function(node, offset) {
      this.impl.extend(unwrapIfNeeded(node), offset);
    },
    getRangeAt: function(index) {
      return wrap(this.impl.getRangeAt(index));
    },
    removeRange: function(range) {
      this.impl.removeRange(unwrap(range));
    },
    selectAllChildren: function(node) {
      this.impl.selectAllChildren(unwrapIfNeeded(node));
    },
    toString: function() {
      return this.impl.toString();
    }
  };

  // WebKit extensions. Not implemented.
  // readonly attribute Node baseNode;
  // readonly attribute long baseOffset;
  // readonly attribute Node extentNode;
  // readonly attribute long extentOffset;
  // [RaisesException] void setBaseAndExtent([Default=Undefined] optional Node baseNode,
  //                       [Default=Undefined] optional long baseOffset,
  //                       [Default=Undefined] optional Node extentNode,
  //                       [Default=Undefined] optional long extentOffset);
  // [RaisesException, ImplementedAs=collapse] void setPosition([Default=Undefined] optional Node node,
  //                  [Default=Undefined] optional long offset);

  registerWrapper(window.Selection, Selection, window.getSelection());

  scope.wrappers.Selection = Selection;

})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var GetElementsByInterface = scope.GetElementsByInterface;
  var Node = scope.wrappers.Node;
  var ParentNodeInterface = scope.ParentNodeInterface;
  var Selection = scope.wrappers.Selection;
  var SelectorsInterface = scope.SelectorsInterface;
  var ShadowRoot = scope.wrappers.ShadowRoot;
  var TreeScope = scope.TreeScope;
  var cloneNode = scope.cloneNode;
  var defineWrapGetter = scope.defineWrapGetter;
  var elementFromPoint = scope.elementFromPoint;
  var forwardMethodsToWrapper = scope.forwardMethodsToWrapper;
  var matchesNames = scope.matchesNames;
  var mixin = scope.mixin;
  var registerWrapper = scope.registerWrapper;
  var renderAllPending = scope.renderAllPending;
  var rewrap = scope.rewrap;
  var unwrap = scope.unwrap;
  var wrap = scope.wrap;
  var wrapEventTargetMethods = scope.wrapEventTargetMethods;
  var wrapNodeList = scope.wrapNodeList;

  var implementationTable = new WeakMap();

  function Document(node) {
    Node.call(this, node);
    this.treeScope_ = new TreeScope(this, null);
  }
  Document.prototype = Object.create(Node.prototype);

  defineWrapGetter(Document, 'documentElement');

  // Conceptually both body and head can be in a shadow but suporting that seems
  // overkill at this point.
  defineWrapGetter(Document, 'body');
  defineWrapGetter(Document, 'head');

  // document cannot be overridden so we override a bunch of its methods
  // directly on the instance.

  function wrapMethod(name) {
    var original = document[name];
    Document.prototype[name] = function() {
      return wrap(original.apply(this.impl, arguments));
    };
  }

  [
    'createComment',
    'createDocumentFragment',
    'createElement',
    'createElementNS',
    'createEvent',
    'createEventNS',
    'createRange',
    'createTextNode',
    'getElementById'
  ].forEach(wrapMethod);

  var originalAdoptNode = document.adoptNode;

  function adoptNodeNoRemove(node, doc) {
    originalAdoptNode.call(doc.impl, unwrap(node));
    adoptSubtree(node, doc);
  }

  function adoptSubtree(node, doc) {
    if (node.shadowRoot)
      doc.adoptNode(node.shadowRoot);
    if (node instanceof ShadowRoot)
      adoptOlderShadowRoots(node, doc);
    for (var child = node.firstChild; child; child = child.nextSibling) {
      adoptSubtree(child, doc);
    }
  }

  function adoptOlderShadowRoots(shadowRoot, doc) {
    var oldShadowRoot = shadowRoot.olderShadowRoot;
    if (oldShadowRoot)
      doc.adoptNode(oldShadowRoot);
  }

  var originalGetSelection = document.getSelection;

  mixin(Document.prototype, {
    adoptNode: function(node) {
      if (node.parentNode)
        node.parentNode.removeChild(node);
      adoptNodeNoRemove(node, this);
      return node;
    },
    elementFromPoint: function(x, y) {
      return elementFromPoint(this, this, x, y);
    },
    importNode: function(node, deep) {
      return cloneNode(node, deep, this.impl);
    },
    getSelection: function() {
      renderAllPending();
      return new Selection(originalGetSelection.call(unwrap(this)));
    }
  });

  if (document.registerElement) {
    var originalRegisterElement = document.registerElement;
    Document.prototype.registerElement = function(tagName, object) {
      var prototype, extendsOption;
      if (object !== undefined) {
        prototype = object.prototype;
        extendsOption = object.extends;
      }

      if (!prototype)
        prototype = Object.create(HTMLElement.prototype);


      // If we already used the object as a prototype for another custom
      // element.
      if (scope.nativePrototypeTable.get(prototype)) {
        // TODO(arv): DOMException
        throw new Error('NotSupportedError');
      }

      // Find first object on the prototype chain that already have a native
      // prototype. Keep track of all the objects before that so we can create
      // a similar structure for the native case.
      var proto = Object.getPrototypeOf(prototype);
      var nativePrototype;
      var prototypes = [];
      while (proto) {
        nativePrototype = scope.nativePrototypeTable.get(proto);
        if (nativePrototype)
          break;
        prototypes.push(proto);
        proto = Object.getPrototypeOf(proto);
      }

      if (!nativePrototype) {
        // TODO(arv): DOMException
        throw new Error('NotSupportedError');
      }

      // This works by creating a new prototype object that is empty, but has
      // the native prototype as its proto. The original prototype object
      // passed into register is used as the wrapper prototype.

      var newPrototype = Object.create(nativePrototype);
      for (var i = prototypes.length - 1; i >= 0; i--) {
        newPrototype = Object.create(newPrototype);
      }

      // Add callbacks if present.
      // Names are taken from:
      //   https://code.google.com/p/chromium/codesearch#chromium/src/third_party/WebKit/Source/bindings/v8/CustomElementConstructorBuilder.cpp&sq=package:chromium&type=cs&l=156
      // and not from the spec since the spec is out of date.
      [
        'createdCallback',
        'attachedCallback',
        'detachedCallback',
        'attributeChangedCallback',
      ].forEach(function(name) {
        var f = prototype[name];
        if (!f)
          return;
        newPrototype[name] = function() {
          // if this element has been wrapped prior to registration,
          // the wrapper is stale; in this case rewrap
          if (!(wrap(this) instanceof CustomElementConstructor)) {
            rewrap(this);
          }
          f.apply(wrap(this), arguments);
        };
      });

      var p = {prototype: newPrototype};
      if (extendsOption)
        p.extends = extendsOption;

      function CustomElementConstructor(node) {
        if (!node) {
          if (extendsOption) {
            return document.createElement(extendsOption, tagName);
          } else {
            return document.createElement(tagName);
          }
        }
        this.impl = node;
      }
      CustomElementConstructor.prototype = prototype;
      CustomElementConstructor.prototype.constructor = CustomElementConstructor;

      scope.constructorTable.set(newPrototype, CustomElementConstructor);
      scope.nativePrototypeTable.set(prototype, newPrototype);

      // registration is synchronous so do it last
      var nativeConstructor = originalRegisterElement.call(unwrap(this),
          tagName, p);
      return CustomElementConstructor;
    };

    forwardMethodsToWrapper([
      window.HTMLDocument || window.Document,  // Gecko adds these to HTMLDocument
    ], [
      'registerElement',
    ]);
  }

  // We also override some of the methods on document.body and document.head
  // for convenience.
  forwardMethodsToWrapper([
    window.HTMLBodyElement,
    window.HTMLDocument || window.Document,  // Gecko adds these to HTMLDocument
    window.HTMLHeadElement,
    window.HTMLHtmlElement,
  ], [
    'appendChild',
    'compareDocumentPosition',
    'contains',
    'getElementsByClassName',
    'getElementsByTagName',
    'getElementsByTagNameNS',
    'insertBefore',
    'querySelector',
    'querySelectorAll',
    'removeChild',
    'replaceChild',
  ].concat(matchesNames));

  forwardMethodsToWrapper([
    window.HTMLDocument || window.Document,  // Gecko adds these to HTMLDocument
  ], [
    'adoptNode',
    'importNode',
    'contains',
    'createComment',
    'createDocumentFragment',
    'createElement',
    'createElementNS',
    'createEvent',
    'createEventNS',
    'createRange',
    'createTextNode',
    'elementFromPoint',
    'getElementById',
    'getSelection',
  ]);

  mixin(Document.prototype, GetElementsByInterface);
  mixin(Document.prototype, ParentNodeInterface);
  mixin(Document.prototype, SelectorsInterface);

  mixin(Document.prototype, {
    get implementation() {
      var implementation = implementationTable.get(this);
      if (implementation)
        return implementation;
      implementation =
          new DOMImplementation(unwrap(this).implementation);
      implementationTable.set(this, implementation);
      return implementation;
    }
  });

  registerWrapper(window.Document, Document,
      document.implementation.createHTMLDocument(''));

  // Both WebKit and Gecko uses HTMLDocument for document. HTML5/DOM only has
  // one Document interface and IE implements the standard correctly.
  if (window.HTMLDocument)
    registerWrapper(window.HTMLDocument, Document);

  wrapEventTargetMethods([
    window.HTMLBodyElement,
    window.HTMLDocument || window.Document,  // Gecko adds these to HTMLDocument
    window.HTMLHeadElement,
  ]);

  function DOMImplementation(impl) {
    this.impl = impl;
  }

  function wrapImplMethod(constructor, name) {
    var original = document.implementation[name];
    constructor.prototype[name] = function() {
      return wrap(original.apply(this.impl, arguments));
    };
  }

  function forwardImplMethod(constructor, name) {
    var original = document.implementation[name];
    constructor.prototype[name] = function() {
      return original.apply(this.impl, arguments);
    };
  }

  wrapImplMethod(DOMImplementation, 'createDocumentType');
  wrapImplMethod(DOMImplementation, 'createDocument');
  wrapImplMethod(DOMImplementation, 'createHTMLDocument');
  forwardImplMethod(DOMImplementation, 'hasFeature');

  registerWrapper(window.DOMImplementation, DOMImplementation);

  forwardMethodsToWrapper([
    window.DOMImplementation,
  ], [
    'createDocumentType',
    'createDocument',
    'createHTMLDocument',
    'hasFeature',
  ]);

  scope.adoptNodeNoRemove = adoptNodeNoRemove;
  scope.wrappers.DOMImplementation = DOMImplementation;
  scope.wrappers.Document = Document;

})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var EventTarget = scope.wrappers.EventTarget;
  var Selection = scope.wrappers.Selection;
  var mixin = scope.mixin;
  var registerWrapper = scope.registerWrapper;
  var renderAllPending = scope.renderAllPending;
  var unwrap = scope.unwrap;
  var unwrapIfNeeded = scope.unwrapIfNeeded;
  var wrap = scope.wrap;

  var OriginalWindow = window.Window;
  var originalGetComputedStyle = window.getComputedStyle;
  var originalGetSelection = window.getSelection;

  function Window(impl) {
    EventTarget.call(this, impl);
  }
  Window.prototype = Object.create(EventTarget.prototype);

  OriginalWindow.prototype.getComputedStyle = function(el, pseudo) {
    return wrap(this || window).getComputedStyle(unwrapIfNeeded(el), pseudo);
  };

  OriginalWindow.prototype.getSelection = function() {
    return wrap(this || window).getSelection();
  };

  // Work around for https://bugzilla.mozilla.org/show_bug.cgi?id=943065
  delete window.getComputedStyle;
  delete window.getSelection;

  ['addEventListener', 'removeEventListener', 'dispatchEvent'].forEach(
      function(name) {
        OriginalWindow.prototype[name] = function() {
          var w = wrap(this || window);
          return w[name].apply(w, arguments);
        };

        // Work around for https://bugzilla.mozilla.org/show_bug.cgi?id=943065
        delete window[name];
      });

  mixin(Window.prototype, {
    getComputedStyle: function(el, pseudo) {
      renderAllPending();
      return originalGetComputedStyle.call(unwrap(this), unwrapIfNeeded(el),
                                           pseudo);
    },
    getSelection: function() {
      renderAllPending();
      return new Selection(originalGetSelection.call(unwrap(this)));
    },
  });

  registerWrapper(OriginalWindow, Window);

  scope.wrappers.Window = Window;

})(window.ShadowDOMPolyfill);

/**
 * Copyright 2014 The Polymer Authors. All rights reserved.
 * Use of this source code is goverened by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {
  'use strict';

  var unwrap = scope.unwrap;

  // DataTransfer (Clipboard in old Blink/WebKit) has a single method that
  // requires wrapping. Since it is only a method we do not need a real wrapper,
  // we can just override the method.

  var OriginalDataTransfer = window.DataTransfer || window.Clipboard;
  var OriginalDataTransferSetDragImage =
      OriginalDataTransfer.prototype.setDragImage;

  OriginalDataTransfer.prototype.setDragImage = function(image, x, y) {
    OriginalDataTransferSetDragImage.call(this, unwrap(image), x, y);
  };

})(window.ShadowDOMPolyfill);

// Copyright 2013 The Polymer Authors. All rights reserved.
// Use of this source code is goverened by a BSD-style
// license that can be found in the LICENSE file.

(function(scope) {
  'use strict';

  var isWrapperFor = scope.isWrapperFor;

  // This is a list of the elements we currently override the global constructor
  // for.
  var elements = {
    'a': 'HTMLAnchorElement',
    // Do not create an applet element by default since it shows a warning in
    // IE.
    // https://github.com/Polymer/polymer/issues/217
    // 'applet': 'HTMLAppletElement',
    'area': 'HTMLAreaElement',
    'audio': 'HTMLAudioElement',
    'base': 'HTMLBaseElement',
    'body': 'HTMLBodyElement',
    'br': 'HTMLBRElement',
    'button': 'HTMLButtonElement',
    'canvas': 'HTMLCanvasElement',
    'caption': 'HTMLTableCaptionElement',
    'col': 'HTMLTableColElement',
    // 'command': 'HTMLCommandElement',  // Not fully implemented in Gecko.
    'content': 'HTMLContentElement',
    'data': 'HTMLDataElement',
    'datalist': 'HTMLDataListElement',
    'del': 'HTMLModElement',
    'dir': 'HTMLDirectoryElement',
    'div': 'HTMLDivElement',
    'dl': 'HTMLDListElement',
    'embed': 'HTMLEmbedElement',
    'fieldset': 'HTMLFieldSetElement',
    'font': 'HTMLFontElement',
    'form': 'HTMLFormElement',
    'frame': 'HTMLFrameElement',
    'frameset': 'HTMLFrameSetElement',
    'h1': 'HTMLHeadingElement',
    'head': 'HTMLHeadElement',
    'hr': 'HTMLHRElement',
    'html': 'HTMLHtmlElement',
    'iframe': 'HTMLIFrameElement',
    'img': 'HTMLImageElement',
    'input': 'HTMLInputElement',
    'keygen': 'HTMLKeygenElement',
    'label': 'HTMLLabelElement',
    'legend': 'HTMLLegendElement',
    'li': 'HTMLLIElement',
    'link': 'HTMLLinkElement',
    'map': 'HTMLMapElement',
    'marquee': 'HTMLMarqueeElement',
    'menu': 'HTMLMenuElement',
    'menuitem': 'HTMLMenuItemElement',
    'meta': 'HTMLMetaElement',
    'meter': 'HTMLMeterElement',
    'object': 'HTMLObjectElement',
    'ol': 'HTMLOListElement',
    'optgroup': 'HTMLOptGroupElement',
    'option': 'HTMLOptionElement',
    'output': 'HTMLOutputElement',
    'p': 'HTMLParagraphElement',
    'param': 'HTMLParamElement',
    'pre': 'HTMLPreElement',
    'progress': 'HTMLProgressElement',
    'q': 'HTMLQuoteElement',
    'script': 'HTMLScriptElement',
    'select': 'HTMLSelectElement',
    'shadow': 'HTMLShadowElement',
    'source': 'HTMLSourceElement',
    'span': 'HTMLSpanElement',
    'style': 'HTMLStyleElement',
    'table': 'HTMLTableElement',
    'tbody': 'HTMLTableSectionElement',
    // WebKit and Moz are wrong:
    // https://bugs.webkit.org/show_bug.cgi?id=111469
    // https://bugzilla.mozilla.org/show_bug.cgi?id=848096
    // 'td': 'HTMLTableCellElement',
    'template': 'HTMLTemplateElement',
    'textarea': 'HTMLTextAreaElement',
    'thead': 'HTMLTableSectionElement',
    'time': 'HTMLTimeElement',
    'title': 'HTMLTitleElement',
    'tr': 'HTMLTableRowElement',
    'track': 'HTMLTrackElement',
    'ul': 'HTMLUListElement',
    'video': 'HTMLVideoElement',
  };

  function overrideConstructor(tagName) {
    var nativeConstructorName = elements[tagName];
    var nativeConstructor = window[nativeConstructorName];
    if (!nativeConstructor)
      return;
    var element = document.createElement(tagName);
    var wrapperConstructor = element.constructor;
    window[nativeConstructorName] = wrapperConstructor;
  }

  Object.keys(elements).forEach(overrideConstructor);

  Object.getOwnPropertyNames(scope.wrappers).forEach(function(name) {
    window[name] = scope.wrappers[name]
  });

})(window.ShadowDOMPolyfill);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */
(function() {

  // convenient global
  window.wrap = ShadowDOMPolyfill.wrapIfNeeded;
  window.unwrap = ShadowDOMPolyfill.unwrapIfNeeded;

  // users may want to customize other types
  // TODO(sjmiles): 'button' is now supported by ShadowDOMPolyfill, but
  // I've left this code here in case we need to temporarily patch another
  // type
  /*
  (function() {
    var elts = {HTMLButtonElement: 'button'};
    for (var c in elts) {
      window[c] = function() { throw 'Patched Constructor'; };
      window[c].prototype = Object.getPrototypeOf(
          document.createElement(elts[c]));
    }
  })();
  */

  // patch in prefixed name
  Object.defineProperty(Element.prototype, 'webkitShadowRoot',
      Object.getOwnPropertyDescriptor(Element.prototype, 'shadowRoot'));

  var originalCreateShadowRoot = Element.prototype.createShadowRoot;
  Element.prototype.createShadowRoot = function() {
    var root = originalCreateShadowRoot.call(this);
    CustomElements.watchShadow(this);
    return root;
  };

  Element.prototype.webkitCreateShadowRoot = Element.prototype.createShadowRoot;
})();

/*
 * Copyright 2012 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

/*
  This is a limited shim for ShadowDOM css styling.
  https://dvcs.w3.org/hg/webcomponents/raw-file/tip/spec/shadow/index.html#styles
  
  The intention here is to support only the styling features which can be 
  relatively simply implemented. The goal is to allow users to avoid the 
  most obvious pitfalls and do so without compromising performance significantly. 
  For ShadowDOM styling that's not covered here, a set of best practices
  can be provided that should allow users to accomplish more complex styling.

  The following is a list of specific ShadowDOM styling features and a brief
  discussion of the approach used to shim.

  Shimmed features:

  * :host, :host-context: ShadowDOM allows styling of the shadowRoot's host
  element using the :host rule. To shim this feature, the :host styles are 
  reformatted and prefixed with a given scope name and promoted to a 
  document level stylesheet.
  For example, given a scope name of .foo, a rule like this:
  
    :host {
        background: red;
      }
    }
  
  becomes:
  
    .foo {
      background: red;
    }
  
  * encapsultion: Styles defined within ShadowDOM, apply only to 
  dom inside the ShadowDOM. Polymer uses one of two techniques to imlement
  this feature.
  
  By default, rules are prefixed with the host element tag name 
  as a descendant selector. This ensures styling does not leak out of the 'top'
  of the element's ShadowDOM. For example,

  div {
      font-weight: bold;
    }
  
  becomes:

  x-foo div {
      font-weight: bold;
    }
  
  becomes:


  Alternatively, if Platform.ShadowCSS.strictStyling is set to true then 
  selectors are scoped by adding an attribute selector suffix to each
  simple selector that contains the host element tag name. Each element 
  in the element's ShadowDOM template is also given the scope attribute. 
  Thus, these rules match only elements that have the scope attribute.
  For example, given a scope name of x-foo, a rule like this:
  
    div {
      font-weight: bold;
    }
  
  becomes:
  
    div[x-foo] {
      font-weight: bold;
    }

  Note that elements that are dynamically added to a scope must have the scope
  selector added to them manually.

  * upper/lower bound encapsulation: Styles which are defined outside a
  shadowRoot should not cross the ShadowDOM boundary and should not apply
  inside a shadowRoot.

  This styling behavior is not emulated. Some possible ways to do this that 
  were rejected due to complexity and/or performance concerns include: (1) reset
  every possible property for every possible selector for a given scope name;
  (2) re-implement css in javascript.
  
  As an alternative, users should make sure to use selectors
  specific to the scope in which they are working.
  
  * ::distributed: This behavior is not emulated. It's often not necessary
  to style the contents of a specific insertion point and instead, descendants
  of the host element can be styled selectively. Users can also create an 
  extra node around an insertion point and style that node's contents
  via descendent selectors. For example, with a shadowRoot like this:
  
    <style>
      ::content(div) {
        background: red;
      }
    </style>
    <content></content>
  
  could become:
  
    <style>
      / *@polyfill .content-container div * / 
      ::content(div) {
        background: red;
      }
    </style>
    <div class="content-container">
      <content></content>
    </div>
  
  Note the use of @polyfill in the comment above a ShadowDOM specific style
  declaration. This is a directive to the styling shim to use the selector 
  in comments in lieu of the next selector when running under polyfill.
*/
(function(scope) {

var ShadowCSS = {
  strictStyling: false,
  registry: {},
  // Shim styles for a given root associated with a name and extendsName
  // 1. cache root styles by name
  // 2. optionally tag root nodes with scope name
  // 3. shim polyfill directives /* @polyfill */ and /* @polyfill-rule */
  // 4. shim :host and scoping
  shimStyling: function(root, name, extendsName) {
    var scopeStyles = this.prepareRoot(root, name, extendsName);
    var typeExtension = this.isTypeExtension(extendsName);
    var scopeSelector = this.makeScopeSelector(name, typeExtension);
    // use caching to make working with styles nodes easier and to facilitate
    // lookup of extendee
    var cssText = stylesToCssText(scopeStyles, true);
    cssText = this.scopeCssText(cssText, scopeSelector);
    // cache shimmed css on root for user extensibility
    if (root) {
      root.shimmedStyle = cssText;
    }
    // add style to document
    this.addCssToDocument(cssText, name);
  },
  /*
  * Shim a style element with the given selector. Returns cssText that can
  * be included in the document via Platform.ShadowCSS.addCssToDocument(css).
  */
  shimStyle: function(style, selector) {
    return this.shimCssText(style.textContent, selector);
  },
  /*
  * Shim some cssText with the given selector. Returns cssText that can
  * be included in the document via Platform.ShadowCSS.addCssToDocument(css).
  */
  shimCssText: function(cssText, selector) {
    cssText = this.insertDirectives(cssText);
    return this.scopeCssText(cssText, selector);
  },
  makeScopeSelector: function(name, typeExtension) {
    if (name) {
      return typeExtension ? '[is=' + name + ']' : name;
    }
    return '';
  },
  isTypeExtension: function(extendsName) {
    return extendsName && extendsName.indexOf('-') < 0;
  },
  prepareRoot: function(root, name, extendsName) {
    var def = this.registerRoot(root, name, extendsName);
    this.replaceTextInStyles(def.rootStyles, this.insertDirectives);
    // remove existing style elements
    this.removeStyles(root, def.rootStyles);
    // apply strict attr
    if (this.strictStyling) {
      this.applyScopeToContent(root, name);
    }
    return def.scopeStyles;
  },
  removeStyles: function(root, styles) {
    for (var i=0, l=styles.length, s; (i<l) && (s=styles[i]); i++) {
      s.parentNode.removeChild(s);
    }
  },
  registerRoot: function(root, name, extendsName) {
    var def = this.registry[name] = {
      root: root,
      name: name,
      extendsName: extendsName
    }
    var styles = this.findStyles(root);
    def.rootStyles = styles;
    def.scopeStyles = def.rootStyles;
    var extendee = this.registry[def.extendsName];
    if (extendee) {
      def.scopeStyles = extendee.scopeStyles.concat(def.scopeStyles);
    }
    return def;
  },
  findStyles: function(root) {
    if (!root) {
      return [];
    }
    var styles = root.querySelectorAll('style');
    return Array.prototype.filter.call(styles, function(s) {
      return !s.hasAttribute(NO_SHIM_ATTRIBUTE);
    });
  },
  applyScopeToContent: function(root, name) {
    if (root) {
      // add the name attribute to each node in root.
      Array.prototype.forEach.call(root.querySelectorAll('*'),
          function(node) {
            node.setAttribute(name, '');
          });
      // and template contents too
      Array.prototype.forEach.call(root.querySelectorAll('template'),
          function(template) {
            this.applyScopeToContent(template.content, name);
          },
          this);
    }
  },
  insertDirectives: function(cssText) {
    cssText = this.insertPolyfillDirectivesInCssText(cssText);
    return this.insertPolyfillRulesInCssText(cssText);
  },
  /*
   * Process styles to convert native ShadowDOM rules that will trip
   * up the css parser; we rely on decorating the stylesheet with inert rules.
   * 
   * For example, we convert this rule:
   * 
   * polyfill-next-selector { content: ':host menu-item'; }
   * ::content menu-item {
   * 
   * to this:
   * 
   * scopeName menu-item {
   *
  **/
  insertPolyfillDirectivesInCssText: function(cssText) {
    // TODO(sorvell): remove either content or comment
    cssText = cssText.replace(cssCommentNextSelectorRe, function(match, p1) {
      // remove end comment delimiter and add block start
      return p1.slice(0, -2) + '{';
    });
    return cssText.replace(cssContentNextSelectorRe, function(match, p1) {
      return p1 + ' {';
    });
  },
  /*
   * Process styles to add rules which will only apply under the polyfill
   * 
   * For example, we convert this rule:
   * 
   * polyfill-rule {
   *   content: ':host menu-item';
   * ...
   * }
   * 
   * to this:
   * 
   * scopeName menu-item {...}
   *
  **/
  insertPolyfillRulesInCssText: function(cssText) {
    // TODO(sorvell): remove either content or comment
    cssText = cssText.replace(cssCommentRuleRe, function(match, p1) {
      // remove end comment delimiter
      return p1.slice(0, -1);
    });
    return cssText.replace(cssContentRuleRe, function(match, p1, p2, p3) {
      var rule = match.replace(p1, '').replace(p2, '');
      return p3 + rule;
    });
  },
  /* Ensure styles are scoped. Pseudo-scoping takes a rule like:
   * 
   *  .foo {... } 
   *  
   *  and converts this to
   *  
   *  scopeName .foo { ... }
  */
  scopeCssText: function(cssText, scopeSelector) {
    var unscoped = this.extractUnscopedRulesFromCssText(cssText);
    cssText = this.insertPolyfillHostInCssText(cssText);
    cssText = this.convertColonHost(cssText);
    cssText = this.convertColonHostContext(cssText);
    cssText = this.convertCombinators(cssText);
    if (scopeSelector) {
      var self = this, cssText;
      withCssRules(cssText, function(rules) {
        cssText = self.scopeRules(rules, scopeSelector);
      });

    }
    cssText = cssText + '\n' + unscoped;
    return cssText.trim();
  },
  /*
   * Process styles to add rules which will only apply under the polyfill
   * and do not process via CSSOM. (CSSOM is destructive to rules on rare 
   * occasions, e.g. -webkit-calc on Safari.)
   * For example, we convert this rule:
   * 
   * (comment start) @polyfill-unscoped-rule menu-item { 
   * ... } (comment end)
   * 
   * to this:
   * 
   * menu-item {...}
   *
  **/
  extractUnscopedRulesFromCssText: function(cssText) {
    // TODO(sorvell): remove either content or comment
    var r = '', m;
    while (m = cssCommentUnscopedRuleRe.exec(cssText)) {
      r += m[1].slice(0, -1) + '\n\n';
    }
    while (m = cssContentUnscopedRuleRe.exec(cssText)) {
      r += m[0].replace(m[2], '').replace(m[1], m[3]) + '\n\n';
    }
    return r;
  },
  /*
   * convert a rule like :host(.foo) > .bar { }
   *
   * to
   *
   * scopeName.foo > .bar
  */
  convertColonHost: function(cssText) {
    return this.convertColonRule(cssText, cssColonHostRe,
        this.colonHostPartReplacer);
  },
  /*
   * convert a rule like :host-context(.foo) > .bar { }
   *
   * to
   *
   * scopeName.foo > .bar, .foo scopeName > .bar { }
   * 
   * and
   *
   * :host-context(.foo:host) .bar { ... }
   * 
   * to
   * 
   * scopeName.foo .bar { ... }
  */
  convertColonHostContext: function(cssText) {
    return this.convertColonRule(cssText, cssColonHostContextRe,
        this.colonHostContextPartReplacer);
  },
  convertColonRule: function(cssText, regExp, partReplacer) {
    // p1 = :host, p2 = contents of (), p3 rest of rule
    return cssText.replace(regExp, function(m, p1, p2, p3) {
      p1 = polyfillHostNoCombinator;
      if (p2) {
        var parts = p2.split(','), r = [];
        for (var i=0, l=parts.length, p; (i<l) && (p=parts[i]); i++) {
          p = p.trim();
          r.push(partReplacer(p1, p, p3));
        }
        return r.join(',');
      } else {
        return p1 + p3;
      }
    });
  },
  colonHostContextPartReplacer: function(host, part, suffix) {
    if (part.match(polyfillHost)) {
      return this.colonHostPartReplacer(host, part, suffix);
    } else {
      return host + part + suffix + ', ' + part + ' ' + host + suffix;
    }
  },
  colonHostPartReplacer: function(host, part, suffix) {
    return host + part.replace(polyfillHost, '') + suffix;
  },
  /*
   * Convert ^ and ^^ combinators by replacing with space.
  */
  convertCombinators: function(cssText) {
    for (var i=0; i < combinatorsRe.length; i++) {
      cssText = cssText.replace(combinatorsRe[i], ' ');
    }
    return cssText;
  },
  // change a selector like 'div' to 'name div'
  scopeRules: function(cssRules, scopeSelector) {
    var cssText = '';
    if (cssRules) {
      Array.prototype.forEach.call(cssRules, function(rule) {
        if (rule.selectorText && (rule.style && rule.style.cssText)) {
          cssText += this.scopeSelector(rule.selectorText, scopeSelector, 
            this.strictStyling) + ' {\n\t';
          cssText += this.propertiesFromRule(rule) + '\n}\n\n';
        } else if (rule.type === CSSRule.MEDIA_RULE) {
          cssText += '@media ' + rule.media.mediaText + ' {\n';
          cssText += this.scopeRules(rule.cssRules, scopeSelector);
          cssText += '\n}\n\n';
        } else if (rule.cssText) {
          cssText += rule.cssText + '\n\n';
        }
      }, this);
    }
    return cssText;
  },
  scopeSelector: function(selector, scopeSelector, strict) {
    var r = [], parts = selector.split(',');
    parts.forEach(function(p) {
      p = p.trim();
      if (this.selectorNeedsScoping(p, scopeSelector)) {
        p = (strict && !p.match(polyfillHostNoCombinator)) ? 
            this.applyStrictSelectorScope(p, scopeSelector) :
            this.applySimpleSelectorScope(p, scopeSelector);
      }
      r.push(p);
    }, this);
    return r.join(', ');
  },
  selectorNeedsScoping: function(selector, scopeSelector) {
    var re = this.makeScopeMatcher(scopeSelector);
    return !selector.match(re);
  },
  makeScopeMatcher: function(scopeSelector) {
    scopeSelector = scopeSelector.replace(/\[/g, '\\[').replace(/\[/g, '\\]');
    return new RegExp('^(' + scopeSelector + ')' + selectorReSuffix, 'm');
  },
  // scope via name and [is=name]
  applySimpleSelectorScope: function(selector, scopeSelector) {
    if (selector.match(polyfillHostRe)) {
      selector = selector.replace(polyfillHostNoCombinator, scopeSelector);
      return selector.replace(polyfillHostRe, scopeSelector + ' ');
    } else {
      return scopeSelector + ' ' + selector;
    }
  },
  // return a selector with [name] suffix on each simple selector
  // e.g. .foo.bar > .zot becomes .foo[name].bar[name] > .zot[name]
  applyStrictSelectorScope: function(selector, scopeSelector) {
    scopeSelector = scopeSelector.replace(/\[is=([^\]]*)\]/g, '$1');
    var splits = [' ', '>', '+', '~'],
      scoped = selector,
      attrName = '[' + scopeSelector + ']';
    splits.forEach(function(sep) {
      var parts = scoped.split(sep);
      scoped = parts.map(function(p) {
        // remove :host since it should be unnecessary
        var t = p.trim().replace(polyfillHostRe, '');
        if (t && (splits.indexOf(t) < 0) && (t.indexOf(attrName) < 0)) {
          p = t.replace(/([^:]*)(:*)(.*)/, '$1' + attrName + '$2$3')
        }
        return p;
      }).join(sep);
    });
    return scoped;
  },
  insertPolyfillHostInCssText: function(selector) {
    return selector.replace(colonHostContextRe, polyfillHostContext).replace(
        colonHostRe, polyfillHost);
  },
  propertiesFromRule: function(rule) {
    var cssText = rule.style.cssText;
    // TODO(sorvell): Safari cssom incorrectly removes quotes from the content
    // property. (https://bugs.webkit.org/show_bug.cgi?id=118045)
    // don't replace attr rules
    if (rule.style.content && !rule.style.content.match(/['"]+|attr/)) {
      cssText = cssText.replace(/content:[^;]*;/g, 'content: \'' + 
          rule.style.content + '\';');
    }
    // TODO(sorvell): we can workaround this issue here, but we need a list
    // of troublesome properties to fix https://github.com/Polymer/platform/issues/53
    //
    // inherit rules can be omitted from cssText
    // TODO(sorvell): remove when Blink bug is fixed:
    // https://code.google.com/p/chromium/issues/detail?id=358273
    var style = rule.style;
    for (var i in style) {
      if (style[i] === 'initial') {
        cssText += i + ': initial; ';
      }
    }
    return cssText;
  },
  replaceTextInStyles: function(styles, action) {
    if (styles && action) {
      if (!(styles instanceof Array)) {
        styles = [styles];
      }
      Array.prototype.forEach.call(styles, function(s) {
        s.textContent = action.call(this, s.textContent);
      }, this);
    }
  },
  addCssToDocument: function(cssText, name) {
    if (cssText.match('@import')) {
      addOwnSheet(cssText, name);
    } else {
      addCssToDocument(cssText);
    }
  }
};

var selectorRe = /([^{]*)({[\s\S]*?})/gim,
    cssCommentRe = /\/\*[^*]*\*+([^/*][^*]*\*+)*\//gim,
    // TODO(sorvell): remove either content or comment
    cssCommentNextSelectorRe = /\/\*\s*@polyfill ([^*]*\*+([^/*][^*]*\*+)*\/)([^{]*?){/gim,
    cssContentNextSelectorRe = /polyfill-next-selector[^}]*content\:[\s]*'([^']*)'[^}]*}([^{]*?){/gim,
    // TODO(sorvell): remove either content or comment
    cssCommentRuleRe = /\/\*\s@polyfill-rule([^*]*\*+([^/*][^*]*\*+)*)\//gim,
    cssContentRuleRe = /(polyfill-rule)[^}]*(content\:[\s]*'([^']*)'[^;]*;)[^}]*}/gim,
    // TODO(sorvell): remove either content or comment
    cssCommentUnscopedRuleRe = /\/\*\s@polyfill-unscoped-rule([^*]*\*+([^/*][^*]*\*+)*)\//gim,
    cssContentUnscopedRuleRe = /(polyfill-unscoped-rule)[^}]*(content\:[\s]*'([^']*)'[^;]*;)[^}]*}/gim,
    cssPseudoRe = /::(x-[^\s{,(]*)/gim,
    cssPartRe = /::part\(([^)]*)\)/gim,
    // note: :host pre-processed to -shadowcsshost.
    polyfillHost = '-shadowcsshost',
    // note: :host-context pre-processed to -shadowcsshostcontext.
    polyfillHostContext = '-shadowcsscontext',
    parenSuffix = ')(?:\\((' +
        '(?:\\([^)(]*\\)|[^)(]*)+?' +
        ')\\))?([^,{]*)';
    cssColonHostRe = new RegExp('(' + polyfillHost + parenSuffix, 'gim'),
    cssColonHostContextRe = new RegExp('(' + polyfillHostContext + parenSuffix, 'gim'),
    selectorReSuffix = '([>\\s~+\[.,{:][\\s\\S]*)?$',
    colonHostRe = /\:host/gim,
    colonHostContextRe = /\:host-context/gim,
    /* host name without combinator */
    polyfillHostNoCombinator = polyfillHost + '-no-combinator',
    polyfillHostRe = new RegExp(polyfillHost, 'gim'),
    polyfillHostContextRe = new RegExp(polyfillHostContext, 'gim'),
    combinatorsRe = [
      /\^\^/g,
      /\^/g,
      /\/shadow\//g,
      /\/shadow-deep\//g,
      /::shadow/g,
      /\/deep\//g
    ];

function stylesToCssText(styles, preserveComments) {
  var cssText = '';
  Array.prototype.forEach.call(styles, function(s) {
    cssText += s.textContent + '\n\n';
  });
  // strip comments for easier processing
  if (!preserveComments) {
    cssText = cssText.replace(cssCommentRe, '');
  }
  return cssText;
}

function cssTextToStyle(cssText) {
  var style = document.createElement('style');
  style.textContent = cssText;
  return style;
}

function cssToRules(cssText) {
  var style = cssTextToStyle(cssText);
  document.head.appendChild(style);
  var rules = [];
  if (style.sheet) {
    // TODO(sorvell): Firefox throws when accessing the rules of a stylesheet
    // with an @import
    // https://bugzilla.mozilla.org/show_bug.cgi?id=625013
    try {
      rules = style.sheet.cssRules;
    } catch(e) {
      //
    }
  } else {
    console.warn('sheet not found', style);
  }
  style.parentNode.removeChild(style);
  return rules;
}

var frame = document.createElement('iframe');
frame.style.display = 'none';

function initFrame() {
  frame.initialized = true;
  document.body.appendChild(frame);
  var doc = frame.contentDocument;
  var base = doc.createElement('base');
  base.href = document.baseURI;
  doc.head.appendChild(base);
}

function inFrame(fn) {
  if (!frame.initialized) {
    initFrame();
  }
  document.body.appendChild(frame);
  fn(frame.contentDocument);
  document.body.removeChild(frame);
}

// TODO(sorvell): use an iframe if the cssText contains an @import to workaround
// https://code.google.com/p/chromium/issues/detail?id=345114
var isChrome = navigator.userAgent.match('Chrome');
function withCssRules(cssText, callback) {
  if (!callback) {
    return;
  }
  var rules;
  if (cssText.match('@import') && isChrome) {
    var style = cssTextToStyle(cssText);
    inFrame(function(doc) {
      doc.head.appendChild(style.impl);
      rules = style.sheet.cssRules;
      callback(rules);
    });
  } else {
    rules = cssToRules(cssText);
    callback(rules);
  }
}

function rulesToCss(cssRules) {
  for (var i=0, css=[]; i < cssRules.length; i++) {
    css.push(cssRules[i].cssText);
  }
  return css.join('\n\n');
}

function addCssToDocument(cssText) {
  if (cssText) {
    getSheet().appendChild(document.createTextNode(cssText));
  }
}

function addOwnSheet(cssText, name) {
  var style = cssTextToStyle(cssText);
  style.setAttribute(name, '');
  style.setAttribute(SHIMMED_ATTRIBUTE, '');
  document.head.appendChild(style);
}

var SHIM_ATTRIBUTE = 'shim-shadowdom';
var SHIMMED_ATTRIBUTE = 'shim-shadowdom-css';
var NO_SHIM_ATTRIBUTE = 'no-shim';

var sheet;
function getSheet() {
  if (!sheet) {
    sheet = document.createElement("style");
    sheet.setAttribute(SHIMMED_ATTRIBUTE, '');
    sheet[SHIMMED_ATTRIBUTE] = true;
  }
  return sheet;
}

// add polyfill stylesheet to document
if (window.ShadowDOMPolyfill) {
  addCssToDocument('style { display: none !important; }\n');
  var doc = wrap(document);
  var head = doc.querySelector('head');
  head.insertBefore(getSheet(), head.childNodes[0]);

  // TODO(sorvell): monkey-patching HTMLImports is abusive;
  // consider a better solution.
  document.addEventListener('DOMContentLoaded', function() {
    var urlResolver = scope.urlResolver;
    
    if (window.HTMLImports && !HTMLImports.useNative) {
      var SHIM_SHEET_SELECTOR = 'link[rel=stylesheet]' +
          '[' + SHIM_ATTRIBUTE + ']';
      var SHIM_STYLE_SELECTOR = 'style[' + SHIM_ATTRIBUTE + ']';
      HTMLImports.importer.documentPreloadSelectors += ',' + SHIM_SHEET_SELECTOR;
      HTMLImports.importer.importsPreloadSelectors += ',' + SHIM_SHEET_SELECTOR;

      HTMLImports.parser.documentSelectors = [
        HTMLImports.parser.documentSelectors,
        SHIM_SHEET_SELECTOR,
        SHIM_STYLE_SELECTOR
      ].join(',');
  
      var originalParseGeneric = HTMLImports.parser.parseGeneric;

      HTMLImports.parser.parseGeneric = function(elt) {
        if (elt[SHIMMED_ATTRIBUTE]) {
          return;
        }
        var style = elt.__importElement || elt;
        if (!style.hasAttribute(SHIM_ATTRIBUTE)) {
          originalParseGeneric.call(this, elt);
          return;
        }
        if (elt.__resource) {
          style = elt.ownerDocument.createElement('style');
          style.textContent = urlResolver.resolveCssText(
              elt.__resource, elt.href);
        } else {
          urlResolver.resolveStyle(style);  
        }
        style.textContent = ShadowCSS.shimStyle(style);
        style.removeAttribute(SHIM_ATTRIBUTE, '');
        style.setAttribute(SHIMMED_ATTRIBUTE, '');
        style[SHIMMED_ATTRIBUTE] = true;
        // place in document
        if (style.parentNode !== head) {
          // replace links in head
          if (elt.parentNode === head) {
            head.replaceChild(style, elt);
          } else {
            head.appendChild(style);
          }
        }
        style.__importParsed = true;
        this.markParsingComplete(elt);
      }

      var hasResource = HTMLImports.parser.hasResource;
      HTMLImports.parser.hasResource = function(node) {
        if (node.localName === 'link' && node.rel === 'stylesheet' &&
            node.hasAttribute(SHIM_ATTRIBUTE)) {
          return (node.__resource);
        } else {
          return hasResource.call(this, node);
        }
      }

    }
  });
}

// exports
scope.ShadowCSS = ShadowCSS;

})(window.Platform);
} else {
/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */
(function() {

  // poor man's adapter for template.content on various platform scenarios
  window.templateContent = window.templateContent || function(inTemplate) {
    return inTemplate.content;
  };

  // so we can call wrap/unwrap without testing for ShadowDOMPolyfill

  window.wrap = window.unwrap = function(n){
    return n;
  }
  
  addEventListener('DOMContentLoaded', function() {
    if (CustomElements.useNative === false) {
      var originalCreateShadowRoot = Element.prototype.createShadowRoot;
      Element.prototype.createShadowRoot = function() {
        var root = originalCreateShadowRoot.call(this);
        CustomElements.watchShadow(this);
        return root;
      };
    }
  });
  
  window.templateContent = function(inTemplate) {
    // if MDV exists, it may need to boostrap this template to reveal content
    if (window.HTMLTemplateElement && HTMLTemplateElement.bootstrap) {
      HTMLTemplateElement.bootstrap(inTemplate);
    }
    // fallback when there is no Shadow DOM polyfill, no MDV polyfill, and no
    // native template support
    if (!inTemplate.content && !inTemplate._content) {
      var frag = document.createDocumentFragment();
      while (inTemplate.firstChild) {
        frag.appendChild(inTemplate.firstChild);
      }
      inTemplate._content = frag;
    }
    return inTemplate.content || inTemplate._content;
  };

})();
}
/* Any copyright is dedicated to the Public Domain.
 * http://creativecommons.org/publicdomain/zero/1.0/ */

(function(scope) {
  'use strict';

  // feature detect for URL constructor
  var hasWorkingUrl = false;
  if (!scope.forceJURL) {
    try {
      var u = new URL('b', 'http://a');
      hasWorkingUrl = u.href === 'http://a/b';
    } catch(e) {}
  }

  if (hasWorkingUrl)
    return;

  var relative = Object.create(null);
  relative['ftp'] = 21;
  relative['file'] = 0;
  relative['gopher'] = 70;
  relative['http'] = 80;
  relative['https'] = 443;
  relative['ws'] = 80;
  relative['wss'] = 443;

  var relativePathDotMapping = Object.create(null);
  relativePathDotMapping['%2e'] = '.';
  relativePathDotMapping['.%2e'] = '..';
  relativePathDotMapping['%2e.'] = '..';
  relativePathDotMapping['%2e%2e'] = '..';

  function isRelativeScheme(scheme) {
    return relative[scheme] !== undefined;
  }

  function invalid() {
    clear.call(this);
    this._isInvalid = true;
  }

  function IDNAToASCII(h) {
    if ('' == h) {
      invalid.call(this)
    }
    // XXX
    return h.toLowerCase()
  }

  function percentEscape(c) {
    var unicode = c.charCodeAt(0);
    if (unicode > 0x20 &&
       unicode < 0x7F &&
       // " # < > ? `
       [0x22, 0x23, 0x3C, 0x3E, 0x3F, 0x60].indexOf(unicode) == -1
      ) {
      return c;
    }
    return encodeURIComponent(c);
  }

  function percentEscapeQuery(c) {
    // XXX This actually needs to encode c using encoding and then
    // convert the bytes one-by-one.

    var unicode = c.charCodeAt(0);
    if (unicode > 0x20 &&
       unicode < 0x7F &&
       // " # < > ` (do not escape '?')
       [0x22, 0x23, 0x3C, 0x3E, 0x60].indexOf(unicode) == -1
      ) {
      return c;
    }
    return encodeURIComponent(c);
  }

  var EOF = undefined,
      ALPHA = /[a-zA-Z]/,
      ALPHANUMERIC = /[a-zA-Z0-9\+\-\.]/;

  function parse(input, stateOverride, base) {
    function err(message) {
      errors.push(message)
    }

    var state = stateOverride || 'scheme start',
        cursor = 0,
        buffer = '',
        seenAt = false,
        seenBracket = false,
        errors = [];

    loop: while ((input[cursor - 1] != EOF || cursor == 0) && !this._isInvalid) {
      var c = input[cursor];
      switch (state) {
        case 'scheme start':
          if (c && ALPHA.test(c)) {
            buffer += c.toLowerCase(); // ASCII-safe
            state = 'scheme';
          } else if (!stateOverride) {
            buffer = '';
            state = 'no scheme';
            continue;
          } else {
            err('Invalid scheme.');
            break loop;
          }
          break;

        case 'scheme':
          if (c && ALPHANUMERIC.test(c)) {
            buffer += c.toLowerCase(); // ASCII-safe
          } else if (':' == c) {
            this._scheme = buffer;
            buffer = '';
            if (stateOverride) {
              break loop;
            }
            if (isRelativeScheme(this._scheme)) {
              this._isRelative = true;
            }
            if ('file' == this._scheme) {
              state = 'relative';
            } else if (this._isRelative && base && base._scheme == this._scheme) {
              state = 'relative or authority';
            } else if (this._isRelative) {
              state = 'authority first slash';
            } else {
              state = 'scheme data';
            }
          } else if (!stateOverride) {
            buffer = '';
            cursor = 0;
            state = 'no scheme';
            continue;
          } else if (EOF == c) {
            break loop;
          } else {
            err('Code point not allowed in scheme: ' + c)
            break loop;
          }
          break;

        case 'scheme data':
          if ('?' == c) {
            query = '?';
            state = 'query';
          } else if ('#' == c) {
            this._fragment = '#';
            state = 'fragment';
          } else {
            // XXX error handling
            if (EOF != c && '\t' != c && '\n' != c && '\r' != c) {
              this._schemeData += percentEscape(c);
            }
          }
          break;

        case 'no scheme':
          if (!base || !(isRelativeScheme(base._scheme))) {
            err('Missing scheme.');
            invalid.call(this);
          } else {
            state = 'relative';
            continue;
          }
          break;

        case 'relative or authority':
          if ('/' == c && '/' == input[cursor+1]) {
            state = 'authority ignore slashes';
          } else {
            err('Expected /, got: ' + c);
            state = 'relative';
            continue
          }
          break;

        case 'relative':
          this._isRelative = true;
          if ('file' != this._scheme)
            this._scheme = base._scheme;
          if (EOF == c) {
            this._host = base._host;
            this._port = base._port;
            this._path = base._path.slice();
            this._query = base._query;
            break loop;
          } else if ('/' == c || '\\' == c) {
            if ('\\' == c)
              err('\\ is an invalid code point.');
            state = 'relative slash';
          } else if ('?' == c) {
            this._host = base._host;
            this._port = base._port;
            this._path = base._path.slice();
            this._query = '?';
            state = 'query';
          } else if ('#' == c) {
            this._host = base._host;
            this._port = base._port;
            this._path = base._path.slice();
            this._query = base._query;
            this._fragment = '#';
            state = 'fragment';
          } else {
            var nextC = input[cursor+1]
            var nextNextC = input[cursor+2]
            if (
              'file' != this._scheme || !ALPHA.test(c) ||
              (nextC != ':' && nextC != '|') ||
              (EOF != nextNextC && '/' != nextNextC && '\\' != nextNextC && '?' != nextNextC && '#' != nextNextC)) {
              this._host = base._host;
              this._port = base._port;
              this._path = base._path.slice();
              this._path.pop();
            }
            state = 'relative path';
            continue;
          }
          break;

        case 'relative slash':
          if ('/' == c || '\\' == c) {
            if ('\\' == c) {
              err('\\ is an invalid code point.');
            }
            if ('file' == this._scheme) {
              state = 'file host';
            } else {
              state = 'authority ignore slashes';
            }
          } else {
            if ('file' != this._scheme) {
              this._host = base._host;
              this._port = base._port;
            }
            state = 'relative path';
            continue;
          }
          break;

        case 'authority first slash':
          if ('/' == c) {
            state = 'authority second slash';
          } else {
            err("Expected '/', got: " + c);
            state = 'authority ignore slashes';
            continue;
          }
          break;

        case 'authority second slash':
          state = 'authority ignore slashes';
          if ('/' != c) {
            err("Expected '/', got: " + c);
            continue;
          }
          break;

        case 'authority ignore slashes':
          if ('/' != c && '\\' != c) {
            state = 'authority';
            continue;
          } else {
            err('Expected authority, got: ' + c);
          }
          break;

        case 'authority':
          if ('@' == c) {
            if (seenAt) {
              err('@ already seen.');
              buffer += '%40';
            }
            seenAt = true;
            for (var i = 0; i < buffer.length; i++) {
              var cp = buffer[i];
              if ('\t' == cp || '\n' == cp || '\r' == cp) {
                err('Invalid whitespace in authority.');
                continue;
              }
              // XXX check URL code points
              if (':' == cp && null === this._password) {
                this._password = '';
                continue;
              }
              var tempC = percentEscape(cp);
              (null !== this._password) ? this._password += tempC : this._username += tempC;
            }
            buffer = '';
          } else if (EOF == c || '/' == c || '\\' == c || '?' == c || '#' == c) {
            cursor -= buffer.length;
            buffer = '';
            state = 'host';
            continue;
          } else {
            buffer += c;
          }
          break;

        case 'file host':
          if (EOF == c || '/' == c || '\\' == c || '?' == c || '#' == c) {
            if (buffer.length == 2 && ALPHA.test(buffer[0]) && (buffer[1] == ':' || buffer[1] == '|')) {
              state = 'relative path';
            } else if (buffer.length == 0) {
              state = 'relative path start';
            } else {
              this._host = IDNAToASCII.call(this, buffer);
              buffer = '';
              state = 'relative path start';
            }
            continue;
          } else if ('\t' == c || '\n' == c || '\r' == c) {
            err('Invalid whitespace in file host.');
          } else {
            buffer += c;
          }
          break;

        case 'host':
        case 'hostname':
          if (':' == c && !seenBracket) {
            // XXX host parsing
            this._host = IDNAToASCII.call(this, buffer);
            buffer = '';
            state = 'port';
            if ('hostname' == stateOverride) {
              break loop;
            }
          } else if (EOF == c || '/' == c || '\\' == c || '?' == c || '#' == c) {
            this._host = IDNAToASCII.call(this, buffer);
            buffer = '';
            state = 'relative path start';
            if (stateOverride) {
              break loop;
            }
            continue;
          } else if ('\t' != c && '\n' != c && '\r' != c) {
            if ('[' == c) {
              seenBracket = true;
            } else if (']' == c) {
              seenBracket = false;
            }
            buffer += c;
          } else {
            err('Invalid code point in host/hostname: ' + c);
          }
          break;

        case 'port':
          if (/[0-9]/.test(c)) {
            buffer += c;
          } else if (EOF == c || '/' == c || '\\' == c || '?' == c || '#' == c || stateOverride) {
            if ('' != buffer) {
              var temp = parseInt(buffer, 10);
              if (temp != relative[this._scheme]) {
                this._port = temp + '';
              }
              buffer = '';
            }
            if (stateOverride) {
              break loop;
            }
            state = 'relative path start';
            continue;
          } else if ('\t' == c || '\n' == c || '\r' == c) {
            err('Invalid code point in port: ' + c);
          } else {
            invalid.call(this);
          }
          break;

        case 'relative path start':
          if ('\\' == c)
            err("'\\' not allowed in path.");
          state = 'relative path';
          if ('/' != c && '\\' != c) {
            continue;
          }
          break;

        case 'relative path':
          if (EOF == c || '/' == c || '\\' == c || (!stateOverride && ('?' == c || '#' == c))) {
            if ('\\' == c) {
              err('\\ not allowed in relative path.');
            }
            var tmp;
            if (tmp = relativePathDotMapping[buffer.toLowerCase()]) {
              buffer = tmp;
            }
            if ('..' == buffer) {
              this._path.pop();
              if ('/' != c && '\\' != c) {
                this._path.push('');
              }
            } else if ('.' == buffer && '/' != c && '\\' != c) {
              this._path.push('');
            } else if ('.' != buffer) {
              if ('file' == this._scheme && this._path.length == 0 && buffer.length == 2 && ALPHA.test(buffer[0]) && buffer[1] == '|') {
                buffer = buffer[0] + ':';
              }
              this._path.push(buffer);
            }
            buffer = '';
            if ('?' == c) {
              this._query = '?';
              state = 'query';
            } else if ('#' == c) {
              this._fragment = '#';
              state = 'fragment';
            }
          } else if ('\t' != c && '\n' != c && '\r' != c) {
            buffer += percentEscape(c);
          }
          break;

        case 'query':
          if (!stateOverride && '#' == c) {
            this._fragment = '#';
            state = 'fragment';
          } else if (EOF != c && '\t' != c && '\n' != c && '\r' != c) {
            this._query += percentEscapeQuery(c);
          }
          break;

        case 'fragment':
          if (EOF != c && '\t' != c && '\n' != c && '\r' != c) {
            this._fragment += c;
          }
          break;
      }

      cursor++;
    }
  }

  function clear() {
    this._scheme = '';
    this._schemeData = '';
    this._username = '';
    this._password = null;
    this._host = '';
    this._port = '';
    this._path = [];
    this._query = '';
    this._fragment = '';
    this._isInvalid = false;
    this._isRelative = false;
  }

  // Does not process domain names or IP addresses.
  // Does not handle encoding for the query parameter.
  function jURL(url, base /* , encoding */) {
    if (base !== undefined && !(base instanceof jURL))
      base = new jURL(String(base));

    this._url = url;
    clear.call(this);

    var input = url.replace(/^[ \t\r\n\f]+|[ \t\r\n\f]+$/g, '');
    // encoding = encoding || 'utf-8'

    parse.call(this, input, null, base);
  }

  jURL.prototype = {
    get href() {
      if (this._isInvalid)
        return this._url;

      var authority = '';
      if ('' != this._username || null != this._password) {
        authority = this._username +
            (null != this._password ? ':' + this._password : '') + '@';
      }

      return this.protocol +
          (this._isRelative ? '//' + authority + this.host : '') +
          this.pathname + this._query + this._fragment;
    },
    set href(href) {
      clear.call(this);
      parse.call(this, href);
    },

    get protocol() {
      return this._scheme + ':';
    },
    set protocol(protocol) {
      if (this._isInvalid)
        return;
      parse.call(this, protocol + ':', 'scheme start');
    },

    get host() {
      return this._isInvalid ? '' : this._port ?
          this._host + ':' + this._port : this._host;
    },
    set host(host) {
      if (this._isInvalid || !this._isRelative)
        return;
      parse.call(this, host, 'host');
    },

    get hostname() {
      return this._host;
    },
    set hostname(hostname) {
      if (this._isInvalid || !this._isRelative)
        return;
      parse.call(this, hostname, 'hostname');
    },

    get port() {
      return this._port;
    },
    set port(port) {
      if (this._isInvalid || !this._isRelative)
        return;
      parse.call(this, port, 'port');
    },

    get pathname() {
      return this._isInvalid ? '' : this._isRelative ?
          '/' + this._path.join('/') : this._schemeData;
    },
    set pathname(pathname) {
      if (this._isInvalid || !this._isRelative)
        return;
      this._path = [];
      parse.call(this, pathname, 'relative path start');
    },

    get search() {
      return this._isInvalid || !this._query || '?' == this._query ?
          '' : this._query;
    },
    set search(search) {
      if (this._isInvalid || !this._isRelative)
        return;
      this._query = '?';
      if ('?' == search[0])
        search = search.slice(1);
      parse.call(this, search, 'query');
    },

    get hash() {
      return this._isInvalid || !this._fragment || '#' == this._fragment ?
          '' : this._fragment;
    },
    set hash(hash) {
      if (this._isInvalid)
        return;
      this._fragment = '#';
      if ('#' == hash[0])
        hash = hash.slice(1);
      parse.call(this, hash, 'fragment');
    }
  };

  scope.URL = jURL;

})(window);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {

// Old versions of iOS do not have bind.

if (!Function.prototype.bind) {
  Function.prototype.bind = function(scope) {
    var self = this;
    var args = Array.prototype.slice.call(arguments, 1);
    return function() {
      var args2 = args.slice();
      args2.push.apply(args2, arguments);
      return self.apply(scope, args2);
    };
  };
}

// mixin

// copy all properties from inProps (et al) to inObj
function mixin(inObj/*, inProps, inMoreProps, ...*/) {
  var obj = inObj || {};
  for (var i = 1; i < arguments.length; i++) {
    var p = arguments[i];
    try {
      for (var n in p) {
        copyProperty(n, p, obj);
      }
    } catch(x) {
    }
  }
  return obj;
}

// copy property inName from inSource object to inTarget object
function copyProperty(inName, inSource, inTarget) {
  var pd = getPropertyDescriptor(inSource, inName);
  Object.defineProperty(inTarget, inName, pd);
}

// get property descriptor for inName on inObject, even if
// inName exists on some link in inObject's prototype chain
function getPropertyDescriptor(inObject, inName) {
  if (inObject) {
    var pd = Object.getOwnPropertyDescriptor(inObject, inName);
    return pd || getPropertyDescriptor(Object.getPrototypeOf(inObject), inName);
  }
}

// export

scope.mixin = mixin;

})(window.Platform);
// Copyright 2011 Google Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

(function(scope) {

  'use strict';

  // polyfill DOMTokenList
  // * add/remove: allow these methods to take multiple classNames
  // * toggle: add a 2nd argument which forces the given state rather
  //  than toggling.

  var add = DOMTokenList.prototype.add;
  var remove = DOMTokenList.prototype.remove;
  DOMTokenList.prototype.add = function() {
    for (var i = 0; i < arguments.length; i++) {
      add.call(this, arguments[i]);
    }
  };
  DOMTokenList.prototype.remove = function() {
    for (var i = 0; i < arguments.length; i++) {
      remove.call(this, arguments[i]);
    }
  };
  DOMTokenList.prototype.toggle = function(name, bool) {
    if (arguments.length == 1) {
      bool = !this.contains(name);
    }
    bool ? this.add(name) : this.remove(name);
  };
  DOMTokenList.prototype.switch = function(oldName, newName) {
    oldName && this.remove(oldName);
    newName && this.add(newName);
  };

  // add array() to NodeList, NamedNodeMap, HTMLCollection

  var ArraySlice = function() {
    return Array.prototype.slice.call(this);
  };

  var namedNodeMap = (window.NamedNodeMap || window.MozNamedAttrMap || {});

  NodeList.prototype.array = ArraySlice;
  namedNodeMap.prototype.array = ArraySlice;
  HTMLCollection.prototype.array = ArraySlice;

  // polyfill performance.now

  if (!window.performance) {
    var start = Date.now();
    // only at millisecond precision
    window.performance = {now: function(){ return Date.now() - start }};
  }

  // polyfill for requestAnimationFrame

  if (!window.requestAnimationFrame) {
    window.requestAnimationFrame = (function() {
      var nativeRaf = window.webkitRequestAnimationFrame ||
        window.mozRequestAnimationFrame;

      return nativeRaf ?
        function(callback) {
          return nativeRaf(function() {
            callback(performance.now());
          });
        } :
        function( callback ){
          return window.setTimeout(callback, 1000 / 60);
        };
    })();
  }

  if (!window.cancelAnimationFrame) {
    window.cancelAnimationFrame = (function() {
      return  window.webkitCancelAnimationFrame ||
        window.mozCancelAnimationFrame ||
        function(id) {
          clearTimeout(id);
        };
    })();
  }

  // utility

  function createDOM(inTagOrNode, inHTML, inAttrs) {
    var dom = typeof inTagOrNode == 'string' ?
        document.createElement(inTagOrNode) : inTagOrNode.cloneNode(true);
    dom.innerHTML = inHTML;
    if (inAttrs) {
      for (var n in inAttrs) {
        dom.setAttribute(n, inAttrs[n]);
      }
    }
    return dom;
  }
  // Make a stub for Polymer() for polyfill purposes; under the HTMLImports
  // polyfill, scripts in the main document run before imports. That means
  // if (1) polymer is imported and (2) Polymer() is called in the main document
  // in a script after the import, 2 occurs before 1. We correct this here
  // by specfiically patching Polymer(); this is not necessary under native
  // HTMLImports.
  var elementDeclarations = [];

  var polymerStub = function(name, dictionary) {
    elementDeclarations.push(arguments);
  }
  window.Polymer = polymerStub;

  // deliver queued delcarations
  scope.deliverDeclarations = function() {
    scope.deliverDeclarations = function() {
     throw 'Possible attempt to load Polymer twice';
    };
    return elementDeclarations;
  }

  // Once DOMContent has loaded, any main document scripts that depend on
  // Polymer() should have run. Calling Polymer() now is an error until
  // polymer is imported.
  window.addEventListener('DOMContentLoaded', function() {
    if (window.Polymer === polymerStub) {
      window.Polymer = function() {
        console.error('You tried to use polymer without loading it first. To ' +
          'load polymer, <link rel="import" href="' + 
          'components/polymer/polymer.html">');
      };
    }
  });

  // exports
  scope.createDOM = createDOM;

})(window.Platform);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

// poor man's adapter for template.content on various platform scenarios
window.templateContent = window.templateContent || function(inTemplate) {
  return inTemplate.content;
};
(function(scope) {
  
  scope = scope || (window.Inspector = {});
  
  var inspector;

  window.sinspect = function(inNode, inProxy) {
    if (!inspector) {
      inspector = window.open('', 'ShadowDOM Inspector', null, true);
      inspector.document.write(inspectorHTML);
      //inspector.document.close();
      inspector.api = {
        shadowize: shadowize
      };
    }
    inspect(inNode || wrap(document.body), inProxy);
  };

  var inspectorHTML = [
    '<!DOCTYPE html>',
    '<html>',
    '  <head>',
    '    <title>ShadowDOM Inspector</title>',
    '    <style>',
    '      body {',
    '      }',
    '      pre {',
    '        font: 9pt "Courier New", monospace;',
    '        line-height: 1.5em;',
    '      }',
    '      tag {',
    '        color: purple;',
    '      }',
    '      ul {',
    '         margin: 0;',
    '         padding: 0;',
    '         list-style: none;',
    '      }',
    '      li {',
    '         display: inline-block;',
    '         background-color: #f1f1f1;',
    '         padding: 4px 6px;',
    '         border-radius: 4px;',
    '         margin-right: 4px;',
    '      }',
    '    </style>',
    '  </head>',
    '  <body>',
    '    <ul id="crumbs">',
    '    </ul>',
    '    <div id="tree"></div>',
    '  </body>',
    '</html>'
  ].join('\n');
  
  var crumbs = [];

  var displayCrumbs = function() {
    // alias our document
    var d = inspector.document;
    // get crumbbar
    var cb = d.querySelector('#crumbs');
    // clear crumbs
    cb.textContent = '';
    // build new crumbs
    for (var i=0, c; c=crumbs[i]; i++) {
      var a = d.createElement('a');
      a.href = '#';
      a.textContent = c.localName;
      a.idx = i;
      a.onclick = function(event) {
        var c;
        while (crumbs.length > this.idx) {
          c = crumbs.pop();
        }
        inspect(c.shadow || c, c);
        event.preventDefault();
      };
      cb.appendChild(d.createElement('li')).appendChild(a);
    }
  };

  var inspect = function(inNode, inProxy) {
    // alias our document
    var d = inspector.document;
    // reset list of drillable nodes
    drillable = [];
    // memoize our crumb proxy
    var proxy = inProxy || inNode;
    crumbs.push(proxy);
    // update crumbs
    displayCrumbs();
    // reflect local tree
    d.body.querySelector('#tree').innerHTML =
        '<pre>' + output(inNode, inNode.childNodes) + '</pre>';
  };

  var forEach = Array.prototype.forEach.call.bind(Array.prototype.forEach);

  var blacklisted = {STYLE:1, SCRIPT:1, "#comment": 1, TEMPLATE: 1};
  var blacklist = function(inNode) {
    return blacklisted[inNode.nodeName];
  };

  var output = function(inNode, inChildNodes, inIndent) {
    if (blacklist(inNode)) {
      return '';
    }
    var indent = inIndent || '';
    if (inNode.localName || inNode.nodeType == 11) {
      var name = inNode.localName || 'shadow-root';
      //inChildNodes = ShadowDOM.localNodes(inNode);
      var info = indent + describe(inNode);
      // if only textNodes
      // TODO(sjmiles): make correct for ShadowDOM
      /*if (!inNode.children.length && inNode.localName !== 'content' && inNode.localName !== 'shadow') {
        info += catTextContent(inChildNodes);
      } else*/ {
        // TODO(sjmiles): native <shadow> has no reference to its projection
        if (name == 'content' /*|| name == 'shadow'*/) {
          inChildNodes = inNode.getDistributedNodes();
        }
        info += '<br/>';
        var ind = indent + '&nbsp;&nbsp;';
        forEach(inChildNodes, function(n) {
          info += output(n, n.childNodes, ind);
        });
        info += indent;
      }
      if (!({br:1}[name])) {
        info += '<tag>&lt;/' + name + '&gt;</tag>';
        info += '<br/>';
      }
    } else {
      var text = inNode.textContent.trim();
      info = text ? indent + '"' + text + '"' + '<br/>' : '';
    }
    return info;
  };

  var catTextContent = function(inChildNodes) {
    var info = '';
    forEach(inChildNodes, function(n) {
      info += n.textContent.trim();
    });
    return info;
  };

  var drillable = [];

  var describe = function(inNode) {
    var tag = '<tag>' + '&lt;';
    var name = inNode.localName || 'shadow-root';
    if (inNode.webkitShadowRoot || inNode.shadowRoot) {
      tag += ' <button idx="' + drillable.length +
        '" onclick="api.shadowize.call(this)">' + name + '</button>';
      drillable.push(inNode);
    } else {
      tag += name || 'shadow-root';
    }
    if (inNode.attributes) {
      forEach(inNode.attributes, function(a) {
        tag += ' ' + a.name + (a.value ? '="' + a.value + '"' : '');
      });
    }
    tag += '&gt;'+ '</tag>';
    return tag;
  };

  // remote api

  shadowize = function() {
    var idx = Number(this.attributes.idx.value);
    //alert(idx);
    var node = drillable[idx];
    if (node) {
      inspect(node.webkitShadowRoot || node.shadowRoot, node)
    } else {
      console.log("bad shadowize node");
      console.dir(this);
    }
  };
  
  // export
  
  scope.output = output;
  
})(window.Inspector);



/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */
(function(scope) {

  // TODO(sorvell): It's desireable to provide a default stylesheet 
  // that's convenient for styling unresolved elements, but
  // it's cumbersome to have to include this manually in every page.
  // It would make sense to put inside some HTMLImport but 
  // the HTMLImports polyfill does not allow loading of stylesheets 
  // that block rendering. Therefore this injection is tolerated here.

  var style = document.createElement('style');
  style.textContent = ''
      + 'body {'
      + 'transition: opacity ease-in 0.2s;' 
      + ' } \n'
      + 'body[unresolved] {'
      + 'opacity: 0; display: block; overflow: hidden;' 
      + ' } \n'
      ;
  var head = document.querySelector('head');
  head.insertBefore(style, head.firstChild);

})(Platform);

(function(scope) {

  function withDependencies(task, depends) {
    depends = depends || [];
    if (!depends.map) {
      depends = [depends];
    }
    return task.apply(this, depends.map(marshal));
  }

  function module(name, dependsOrFactory, moduleFactory) {
    var module;
    switch (arguments.length) {
      case 0:
        return;
      case 1:
        module = null;
        break;
      case 2:
        module = dependsOrFactory.apply(this);
        break;
      default:
        module = withDependencies(moduleFactory, dependsOrFactory);
        break;
    }
    modules[name] = module;
  };

  function marshal(name) {
    return modules[name];
  }

  var modules = {};

  function using(depends, task) {
    HTMLImports.whenImportsReady(function() {
      withDependencies(task, depends);
    });
  };

  // exports

  scope.marshal = marshal;
  scope.module = module;
  scope.using = using;

})(window);
/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */
(function(scope) {

var iterations = 0;
var callbacks = [];
var twiddle = document.createTextNode('');

function endOfMicrotask(callback) {
  twiddle.textContent = iterations++;
  callbacks.push(callback);
}

function atEndOfMicrotask() {
  while (callbacks.length) {
    callbacks.shift()();
  }
}

new (window.MutationObserver || JsMutationObserver)(atEndOfMicrotask)
  .observe(twiddle, {characterData: true})
  ;

// exports

scope.endOfMicrotask = endOfMicrotask;

})(Platform);


/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {

var urlResolver = {
  resolveDom: function(root, url) {
    url = url || root.ownerDocument.baseURI;
    this.resolveAttributes(root, url);
    this.resolveStyles(root, url);
    // handle template.content
    var templates = root.querySelectorAll('template');
    if (templates) {
      for (var i = 0, l = templates.length, t; (i < l) && (t = templates[i]); i++) {
        if (t.content) {
          this.resolveDom(t.content, url);
        }
      }
    }
  },
  resolveTemplate: function(template) {
    this.resolveDom(template.content, template.ownerDocument.baseURI);
  },
  resolveStyles: function(root, url) {
    var styles = root.querySelectorAll('style');
    if (styles) {
      for (var i = 0, l = styles.length, s; (i < l) && (s = styles[i]); i++) {
        this.resolveStyle(s, url);
      }
    }
  },
  resolveStyle: function(style, url) {
    url = url || style.ownerDocument.baseURI;
    style.textContent = this.resolveCssText(style.textContent, url);
  },
  resolveCssText: function(cssText, baseUrl) {
    cssText = replaceUrlsInCssText(cssText, baseUrl, CSS_URL_REGEXP);
    return replaceUrlsInCssText(cssText, baseUrl, CSS_IMPORT_REGEXP);
  },
  resolveAttributes: function(root, url) {
    if (root.hasAttributes && root.hasAttributes()) {
      this.resolveElementAttributes(root, url);
    }
    // search for attributes that host urls
    var nodes = root && root.querySelectorAll(URL_ATTRS_SELECTOR);
    if (nodes) {
      for (var i = 0, l = nodes.length, n; (i < l) && (n = nodes[i]); i++) {
        this.resolveElementAttributes(n, url);
      }
    }
  },
  resolveElementAttributes: function(node, url) {
    url = url || node.ownerDocument.baseURI;
    URL_ATTRS.forEach(function(v) {
      var attr = node.attributes[v];
      if (attr && attr.value &&
         (attr.value.search(URL_TEMPLATE_SEARCH) < 0)) {
        var urlPath = resolveRelativeUrl(url, attr.value);
        attr.value = urlPath;
      }
    });
  }
};

var CSS_URL_REGEXP = /(url\()([^)]*)(\))/g;
var CSS_IMPORT_REGEXP = /(@import[\s]+(?!url\())([^;]*)(;)/g;
var URL_ATTRS = ['href', 'src', 'action'];
var URL_ATTRS_SELECTOR = '[' + URL_ATTRS.join('],[') + ']';
var URL_TEMPLATE_SEARCH = '{{.*}}';

function replaceUrlsInCssText(cssText, baseUrl, regexp) {
  return cssText.replace(regexp, function(m, pre, url, post) {
    var urlPath = url.replace(/["']/g, '');
    urlPath = resolveRelativeUrl(baseUrl, urlPath);
    return pre + '\'' + urlPath + '\'' + post;
  });
}

function resolveRelativeUrl(baseUrl, url) {
  var u = new URL(url, baseUrl);
  return makeDocumentRelPath(u.href);
}

function makeDocumentRelPath(url) {
  var root = document.baseURI;
  var u = new URL(url, root);
  if (u.host === root.host && u.port === root.port &&
      u.protocol === root.protocol) {
    return makeRelPath(root.pathname, u.pathname);
  } else {
    return url;
  }
}

// make a relative path from source to target
function makeRelPath(source, target) {
  var s = source.split('/');
  var t = target.split('/');
  while (s.length && s[0] === t[0]){
    s.shift();
    t.shift();
  }
  for (var i = 0, l = s.length - 1; i < l; i++) {
    t.unshift('..');
  }
  return t.join('/');
}

// exports
scope.urlResolver = urlResolver;

})(Platform);

/*
 * Copyright 2012 The Polymer Authors. All rights reserved.
 * Use of this source code is goverened by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(global) {

  var registrationsTable = new WeakMap();

  // We use setImmediate or postMessage for our future callback.
  var setImmediate = window.msSetImmediate;

  // Use post message to emulate setImmediate.
  if (!setImmediate) {
    var setImmediateQueue = [];
    var sentinel = String(Math.random());
    window.addEventListener('message', function(e) {
      if (e.data === sentinel) {
        var queue = setImmediateQueue;
        setImmediateQueue = [];
        queue.forEach(function(func) {
          func();
        });
      }
    });
    setImmediate = function(func) {
      setImmediateQueue.push(func);
      window.postMessage(sentinel, '*');
    };
  }

  // This is used to ensure that we never schedule 2 callas to setImmediate
  var isScheduled = false;

  // Keep track of observers that needs to be notified next time.
  var scheduledObservers = [];

  /**
   * Schedules |dispatchCallback| to be called in the future.
   * @param {MutationObserver} observer
   */
  function scheduleCallback(observer) {
    scheduledObservers.push(observer);
    if (!isScheduled) {
      isScheduled = true;
      setImmediate(dispatchCallbacks);
    }
  }

  function wrapIfNeeded(node) {
    return window.ShadowDOMPolyfill &&
        window.ShadowDOMPolyfill.wrapIfNeeded(node) ||
        node;
  }

  function dispatchCallbacks() {
    // http://dom.spec.whatwg.org/#mutation-observers

    isScheduled = false; // Used to allow a new setImmediate call above.

    var observers = scheduledObservers;
    scheduledObservers = [];
    // Sort observers based on their creation UID (incremental).
    observers.sort(function(o1, o2) {
      return o1.uid_ - o2.uid_;
    });

    var anyNonEmpty = false;
    observers.forEach(function(observer) {

      // 2.1, 2.2
      var queue = observer.takeRecords();
      // 2.3. Remove all transient registered observers whose observer is mo.
      removeTransientObserversFor(observer);

      // 2.4
      if (queue.length) {
        observer.callback_(queue, observer);
        anyNonEmpty = true;
      }
    });

    // 3.
    if (anyNonEmpty)
      dispatchCallbacks();
  }

  function removeTransientObserversFor(observer) {
    observer.nodes_.forEach(function(node) {
      var registrations = registrationsTable.get(node);
      if (!registrations)
        return;
      registrations.forEach(function(registration) {
        if (registration.observer === observer)
          registration.removeTransientObservers();
      });
    });
  }

  /**
   * This function is used for the "For each registered observer observer (with
   * observer's options as options) in target's list of registered observers,
   * run these substeps:" and the "For each ancestor ancestor of target, and for
   * each registered observer observer (with options options) in ancestor's list
   * of registered observers, run these substeps:" part of the algorithms. The
   * |options.subtree| is checked to ensure that the callback is called
   * correctly.
   *
   * @param {Node} target
   * @param {function(MutationObserverInit):MutationRecord} callback
   */
  function forEachAncestorAndObserverEnqueueRecord(target, callback) {
    for (var node = target; node; node = node.parentNode) {
      var registrations = registrationsTable.get(node);

      if (registrations) {
        for (var j = 0; j < registrations.length; j++) {
          var registration = registrations[j];
          var options = registration.options;

          // Only target ignores subtree.
          if (node !== target && !options.subtree)
            continue;

          var record = callback(options);
          if (record)
            registration.enqueue(record);
        }
      }
    }
  }

  var uidCounter = 0;

  /**
   * The class that maps to the DOM MutationObserver interface.
   * @param {Function} callback.
   * @constructor
   */
  function JsMutationObserver(callback) {
    this.callback_ = callback;
    this.nodes_ = [];
    this.records_ = [];
    this.uid_ = ++uidCounter;
  }

  JsMutationObserver.prototype = {
    observe: function(target, options) {
      target = wrapIfNeeded(target);

      // 1.1
      if (!options.childList && !options.attributes && !options.characterData ||

          // 1.2
          options.attributeOldValue && !options.attributes ||

          // 1.3
          options.attributeFilter && options.attributeFilter.length &&
              !options.attributes ||

          // 1.4
          options.characterDataOldValue && !options.characterData) {

        throw new SyntaxError();
      }

      var registrations = registrationsTable.get(target);
      if (!registrations)
        registrationsTable.set(target, registrations = []);

      // 2
      // If target's list of registered observers already includes a registered
      // observer associated with the context object, replace that registered
      // observer's options with options.
      var registration;
      for (var i = 0; i < registrations.length; i++) {
        if (registrations[i].observer === this) {
          registration = registrations[i];
          registration.removeListeners();
          registration.options = options;
          break;
        }
      }

      // 3.
      // Otherwise, add a new registered observer to target's list of registered
      // observers with the context object as the observer and options as the
      // options, and add target to context object's list of nodes on which it
      // is registered.
      if (!registration) {
        registration = new Registration(this, target, options);
        registrations.push(registration);
        this.nodes_.push(target);
      }

      registration.addListeners();
    },

    disconnect: function() {
      this.nodes_.forEach(function(node) {
        var registrations = registrationsTable.get(node);
        for (var i = 0; i < registrations.length; i++) {
          var registration = registrations[i];
          if (registration.observer === this) {
            registration.removeListeners();
            registrations.splice(i, 1);
            // Each node can only have one registered observer associated with
            // this observer.
            break;
          }
        }
      }, this);
      this.records_ = [];
    },

    takeRecords: function() {
      var copyOfRecords = this.records_;
      this.records_ = [];
      return copyOfRecords;
    }
  };

  /**
   * @param {string} type
   * @param {Node} target
   * @constructor
   */
  function MutationRecord(type, target) {
    this.type = type;
    this.target = target;
    this.addedNodes = [];
    this.removedNodes = [];
    this.previousSibling = null;
    this.nextSibling = null;
    this.attributeName = null;
    this.attributeNamespace = null;
    this.oldValue = null;
  }

  function copyMutationRecord(original) {
    var record = new MutationRecord(original.type, original.target);
    record.addedNodes = original.addedNodes.slice();
    record.removedNodes = original.removedNodes.slice();
    record.previousSibling = original.previousSibling;
    record.nextSibling = original.nextSibling;
    record.attributeName = original.attributeName;
    record.attributeNamespace = original.attributeNamespace;
    record.oldValue = original.oldValue;
    return record;
  };

  // We keep track of the two (possibly one) records used in a single mutation.
  var currentRecord, recordWithOldValue;

  /**
   * Creates a record without |oldValue| and caches it as |currentRecord| for
   * later use.
   * @param {string} oldValue
   * @return {MutationRecord}
   */
  function getRecord(type, target) {
    return currentRecord = new MutationRecord(type, target);
  }

  /**
   * Gets or creates a record with |oldValue| based in the |currentRecord|
   * @param {string} oldValue
   * @return {MutationRecord}
   */
  function getRecordWithOldValue(oldValue) {
    if (recordWithOldValue)
      return recordWithOldValue;
    recordWithOldValue = copyMutationRecord(currentRecord);
    recordWithOldValue.oldValue = oldValue;
    return recordWithOldValue;
  }

  function clearRecords() {
    currentRecord = recordWithOldValue = undefined;
  }

  /**
   * @param {MutationRecord} record
   * @return {boolean} Whether the record represents a record from the current
   * mutation event.
   */
  function recordRepresentsCurrentMutation(record) {
    return record === recordWithOldValue || record === currentRecord;
  }

  /**
   * Selects which record, if any, to replace the last record in the queue.
   * This returns |null| if no record should be replaced.
   *
   * @param {MutationRecord} lastRecord
   * @param {MutationRecord} newRecord
   * @param {MutationRecord}
   */
  function selectRecord(lastRecord, newRecord) {
    if (lastRecord === newRecord)
      return lastRecord;

    // Check if the the record we are adding represents the same record. If
    // so, we keep the one with the oldValue in it.
    if (recordWithOldValue && recordRepresentsCurrentMutation(lastRecord))
      return recordWithOldValue;

    return null;
  }

  /**
   * Class used to represent a registered observer.
   * @param {MutationObserver} observer
   * @param {Node} target
   * @param {MutationObserverInit} options
   * @constructor
   */
  function Registration(observer, target, options) {
    this.observer = observer;
    this.target = target;
    this.options = options;
    this.transientObservedNodes = [];
  }

  Registration.prototype = {
    enqueue: function(record) {
      var records = this.observer.records_;
      var length = records.length;

      // There are cases where we replace the last record with the new record.
      // For example if the record represents the same mutation we need to use
      // the one with the oldValue. If we get same record (this can happen as we
      // walk up the tree) we ignore the new record.
      if (records.length > 0) {
        var lastRecord = records[length - 1];
        var recordToReplaceLast = selectRecord(lastRecord, record);
        if (recordToReplaceLast) {
          records[length - 1] = recordToReplaceLast;
          return;
        }
      } else {
        scheduleCallback(this.observer);
      }

      records[length] = record;
    },

    addListeners: function() {
      this.addListeners_(this.target);
    },

    addListeners_: function(node) {
      var options = this.options;
      if (options.attributes)
        node.addEventListener('DOMAttrModified', this, true);

      if (options.characterData)
        node.addEventListener('DOMCharacterDataModified', this, true);

      if (options.childList)
        node.addEventListener('DOMNodeInserted', this, true);

      if (options.childList || options.subtree)
        node.addEventListener('DOMNodeRemoved', this, true);
    },

    removeListeners: function() {
      this.removeListeners_(this.target);
    },

    removeListeners_: function(node) {
      var options = this.options;
      if (options.attributes)
        node.removeEventListener('DOMAttrModified', this, true);

      if (options.characterData)
        node.removeEventListener('DOMCharacterDataModified', this, true);

      if (options.childList)
        node.removeEventListener('DOMNodeInserted', this, true);

      if (options.childList || options.subtree)
        node.removeEventListener('DOMNodeRemoved', this, true);
    },

    /**
     * Adds a transient observer on node. The transient observer gets removed
     * next time we deliver the change records.
     * @param {Node} node
     */
    addTransientObserver: function(node) {
      // Don't add transient observers on the target itself. We already have all
      // the required listeners set up on the target.
      if (node === this.target)
        return;

      this.addListeners_(node);
      this.transientObservedNodes.push(node);
      var registrations = registrationsTable.get(node);
      if (!registrations)
        registrationsTable.set(node, registrations = []);

      // We know that registrations does not contain this because we already
      // checked if node === this.target.
      registrations.push(this);
    },

    removeTransientObservers: function() {
      var transientObservedNodes = this.transientObservedNodes;
      this.transientObservedNodes = [];

      transientObservedNodes.forEach(function(node) {
        // Transient observers are never added to the target.
        this.removeListeners_(node);

        var registrations = registrationsTable.get(node);
        for (var i = 0; i < registrations.length; i++) {
          if (registrations[i] === this) {
            registrations.splice(i, 1);
            // Each node can only have one registered observer associated with
            // this observer.
            break;
          }
        }
      }, this);
    },

    handleEvent: function(e) {
      // Stop propagation since we are managing the propagation manually.
      // This means that other mutation events on the page will not work
      // correctly but that is by design.
      e.stopImmediatePropagation();

      switch (e.type) {
        case 'DOMAttrModified':
          // http://dom.spec.whatwg.org/#concept-mo-queue-attributes

          var name = e.attrName;
          var namespace = e.relatedNode.namespaceURI;
          var target = e.target;

          // 1.
          var record = new getRecord('attributes', target);
          record.attributeName = name;
          record.attributeNamespace = namespace;

          // 2.
          var oldValue =
              e.attrChange === MutationEvent.ADDITION ? null : e.prevValue;

          forEachAncestorAndObserverEnqueueRecord(target, function(options) {
            // 3.1, 4.2
            if (!options.attributes)
              return;

            // 3.2, 4.3
            if (options.attributeFilter && options.attributeFilter.length &&
                options.attributeFilter.indexOf(name) === -1 &&
                options.attributeFilter.indexOf(namespace) === -1) {
              return;
            }
            // 3.3, 4.4
            if (options.attributeOldValue)
              return getRecordWithOldValue(oldValue);

            // 3.4, 4.5
            return record;
          });

          break;

        case 'DOMCharacterDataModified':
          // http://dom.spec.whatwg.org/#concept-mo-queue-characterdata
          var target = e.target;

          // 1.
          var record = getRecord('characterData', target);

          // 2.
          var oldValue = e.prevValue;


          forEachAncestorAndObserverEnqueueRecord(target, function(options) {
            // 3.1, 4.2
            if (!options.characterData)
              return;

            // 3.2, 4.3
            if (options.characterDataOldValue)
              return getRecordWithOldValue(oldValue);

            // 3.3, 4.4
            return record;
          });

          break;

        case 'DOMNodeRemoved':
          this.addTransientObserver(e.target);
          // Fall through.
        case 'DOMNodeInserted':
          // http://dom.spec.whatwg.org/#concept-mo-queue-childlist
          var target = e.relatedNode;
          var changedNode = e.target;
          var addedNodes, removedNodes;
          if (e.type === 'DOMNodeInserted') {
            addedNodes = [changedNode];
            removedNodes = [];
          } else {

            addedNodes = [];
            removedNodes = [changedNode];
          }
          var previousSibling = changedNode.previousSibling;
          var nextSibling = changedNode.nextSibling;

          // 1.
          var record = getRecord('childList', target);
          record.addedNodes = addedNodes;
          record.removedNodes = removedNodes;
          record.previousSibling = previousSibling;
          record.nextSibling = nextSibling;

          forEachAncestorAndObserverEnqueueRecord(target, function(options) {
            // 2.1, 3.2
            if (!options.childList)
              return;

            // 2.2, 3.3
            return record;
          });

      }

      clearRecords();
    }
  };

  global.JsMutationObserver = JsMutationObserver;

  if (!global.MutationObserver)
    global.MutationObserver = JsMutationObserver;


})(this);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */
window.HTMLImports = window.HTMLImports || {flags:{}};
/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {

  // imports
  var path = scope.path;
  var xhr = scope.xhr;
  var flags = scope.flags;

  // TODO(sorvell): this loader supports a dynamic list of urls
  // and an oncomplete callback that is called when the loader is done.
  // The polyfill currently does *not* need this dynamism or the onComplete
  // concept. Because of this, the loader could be simplified quite a bit.
  var Loader = function(onLoad, onComplete) {
    this.cache = {};
    this.onload = onLoad;
    this.oncomplete = onComplete;
    this.inflight = 0;
    this.pending = {};
  };

  Loader.prototype = {
    addNodes: function(nodes) {
      // number of transactions to complete
      this.inflight += nodes.length;
      // commence transactions
      for (var i=0, l=nodes.length, n; (i<l) && (n=nodes[i]); i++) {
        this.require(n);
      }
      // anything to do?
      this.checkDone();
    },
    addNode: function(node) {
      // number of transactions to complete
      this.inflight++;
      // commence transactions
      this.require(node);
      // anything to do?
      this.checkDone();
    },
    require: function(elt) {
      var url = elt.src || elt.href;
      // ensure we have a standard url that can be used
      // reliably for deduping.
      // TODO(sjmiles): ad-hoc
      elt.__nodeUrl = url;
      // deduplication
      if (!this.dedupe(url, elt)) {
        // fetch this resource
        this.fetch(url, elt);
      }
    },
    dedupe: function(url, elt) {
      if (this.pending[url]) {
        // add to list of nodes waiting for inUrl
        this.pending[url].push(elt);
        // don't need fetch
        return true;
      }
      var resource;
      if (this.cache[url]) {
        this.onload(url, elt, this.cache[url]);
        // finished this transaction
        this.tail();
        // don't need fetch
        return true;
      }
      // first node waiting for inUrl
      this.pending[url] = [elt];
      // need fetch (not a dupe)
      return false;
    },
    fetch: function(url, elt) {
      flags.load && console.log('fetch', url, elt);
      if (url.match(/^data:/)) {
        // Handle Data URI Scheme
        var pieces = url.split(',');
        var header = pieces[0];
        var body = pieces[1];
        if(header.indexOf(';base64') > -1) {
          body = atob(body);
        } else {
          body = decodeURIComponent(body);
        }
        setTimeout(function() {
            this.receive(url, elt, null, body);
        }.bind(this), 0);
      } else {
        var receiveXhr = function(err, resource) {
          this.receive(url, elt, err, resource);
        }.bind(this);
        xhr.load(url, receiveXhr);
        // TODO(sorvell): blocked on)
        // https://code.google.com/p/chromium/issues/detail?id=257221
        // xhr'ing for a document makes scripts in imports runnable; otherwise
        // they are not; however, it requires that we have doctype=html in
        // the import which is unacceptable. This is only needed on Chrome
        // to avoid the bug above.
        /*
        if (isDocumentLink(elt)) {
          xhr.loadDocument(url, receiveXhr);
        } else {
          xhr.load(url, receiveXhr);
        }
        */
      }
    },
    receive: function(url, elt, err, resource) {
      this.cache[url] = resource;
      var $p = this.pending[url];
      for (var i=0, l=$p.length, p; (i<l) && (p=$p[i]); i++) {
        //if (!err) {
          this.onload(url, p, resource);
        //}
        this.tail();
      }
      this.pending[url] = null;
    },
    tail: function() {
      --this.inflight;
      this.checkDone();
    },
    checkDone: function() {
      if (!this.inflight) {
        this.oncomplete();
      }
    }
  };

  xhr = xhr || {
    async: true,
    ok: function(request) {
      return (request.status >= 200 && request.status < 300)
          || (request.status === 304)
          || (request.status === 0);
    },
    load: function(url, next, nextContext) {
      var request = new XMLHttpRequest();
      if (scope.flags.debug || scope.flags.bust) {
        url += '?' + Math.random();
      }
      request.open('GET', url, xhr.async);
      request.addEventListener('readystatechange', function(e) {
        if (request.readyState === 4) {
          next.call(nextContext, !xhr.ok(request) && request,
              request.response || request.responseText, url);
        }
      });
      request.send();
      return request;
    },
    loadDocument: function(url, next, nextContext) {
      this.load(url, next, nextContext).responseType = 'document';
    }
  };

  // exports
  scope.xhr = xhr;
  scope.Loader = Loader;

})(window.HTMLImports);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {

var IMPORT_LINK_TYPE = 'import';
var flags = scope.flags;
var isIe = /Trident/.test(navigator.userAgent);
// TODO(sorvell): SD polyfill intrusion
var mainDoc = window.ShadowDOMPolyfill ? 
    window.ShadowDOMPolyfill.wrapIfNeeded(document) : document;

// importParser
// highlander object to manage parsing of imports
// parses import related elements
// and ensures proper parse order
// parse order is enforced by crawling the tree and monitoring which elements
// have been parsed; async parsing is also supported.

// highlander object for parsing a document tree
var importParser = {
  // parse selectors for main document elements
  documentSelectors: 'link[rel=' + IMPORT_LINK_TYPE + ']',
  // parse selectors for import document elements
  importsSelectors: [
    'link[rel=' + IMPORT_LINK_TYPE + ']',
    'link[rel=stylesheet]',
    'style',
    'script:not([type])',
    'script[type="text/javascript"]'
  ].join(','),
  map: {
    link: 'parseLink',
    script: 'parseScript',
    style: 'parseStyle'
  },
  // try to parse the next import in the tree
  parseNext: function() {
    var next = this.nextToParse();
    if (next) {
      this.parse(next);
    }
  },
  parse: function(elt) {
    if (this.isParsed(elt)) {
      flags.parse && console.log('[%s] is already parsed', elt.localName);
      return;
    }
    var fn = this[this.map[elt.localName]];
    if (fn) {
      this.markParsing(elt);
      fn.call(this, elt);
    }
  },
  // only 1 element may be parsed at a time; parsing is async so, each
  // parsing implementation must inform the system that parsing is complete
  // via markParsingComplete.
  markParsing: function(elt) {
    flags.parse && console.log('parsing', elt);
    this.parsingElement = elt;
  },
  markParsingComplete: function(elt) {
    elt.__importParsed = true;
    if (elt.__importElement) {
      elt.__importElement.__importParsed = true;
    }
    this.parsingElement = null;
    flags.parse && console.log('completed', elt);
    this.parseNext();
  },
  parseImport: function(elt) {
    elt.import.__importParsed = true;
    // TODO(sorvell): consider if there's a better way to do this;
    // expose an imports parsing hook; this is needed, for example, by the
    // CustomElements polyfill.
    if (HTMLImports.__importsParsingHook) {
      HTMLImports.__importsParsingHook(elt);
    }
    // fire load event
    if (elt.__resource) {
      elt.dispatchEvent(new CustomEvent('load', {bubbles: false}));    
    } else {
      elt.dispatchEvent(new CustomEvent('error', {bubbles: false}));
    }
    // TODO(sorvell): workaround for Safari addEventListener not working
    // for elements not in the main document.
    if (elt.__pending) {
      var fn;
      while (elt.__pending.length) {
        fn = elt.__pending.shift();
        if (fn) {
          fn({target: elt});
        }
      }
    }
    this.markParsingComplete(elt);
  },
  parseLink: function(linkElt) {
    if (nodeIsImport(linkElt)) {
      this.parseImport(linkElt);
    } else {
      // make href absolute
      linkElt.href = linkElt.href;
      this.parseGeneric(linkElt);
    }
  },
  parseStyle: function(elt) {
    // TODO(sorvell): style element load event can just not fire so clone styles
    var src = elt;
    elt = cloneStyle(elt);
    elt.__importElement = src;
    this.parseGeneric(elt);
  },
  parseGeneric: function(elt) {
    this.trackElement(elt);
    document.head.appendChild(elt);
  },
  // tracks when a loadable element has loaded
  trackElement: function(elt, callback) {
    var self = this;
    var done = function(e) {
      if (callback) {
        callback(e);
      }
      self.markParsingComplete(elt);
    };
    elt.addEventListener('load', done);
    elt.addEventListener('error', done);

    // NOTE: IE does not fire "load" event for styles that have already loaded
    // This is in violation of the spec, so we try our hardest to work around it
    if (isIe && elt.localName === 'style') {
      var fakeLoad = false;
      // If there's not @import in the textContent, assume it has loaded
      if (elt.textContent.indexOf('@import') == -1) {
        fakeLoad = true;
      // if we have a sheet, we have been parsed
      } else if (elt.sheet) {
        fakeLoad = true;
        var csr = elt.sheet.cssRules;
        var len = csr ? csr.length : 0;
        // search the rules for @import's
        for (var i = 0, r; (i < len) && (r = csr[i]); i++) {
          if (r.type === CSSRule.IMPORT_RULE) {
            // if every @import has resolved, fake the load
            fakeLoad = fakeLoad && Boolean(r.styleSheet);
          }
        }
      }
      // dispatch a fake load event and continue parsing
      if (fakeLoad) {
        elt.dispatchEvent(new CustomEvent('load', {bubbles: false}));
      }
    }
  },
  // NOTE: execute scripts by injecting them and watching for the load/error
  // event. Inline scripts are handled via dataURL's because browsers tend to
  // provide correct parsing errors in this case. If this has any compatibility
  // issues, we can switch to injecting the inline script with textContent.
  // Scripts with dataURL's do not appear to generate load events and therefore
  // we assume they execute synchronously.
  parseScript: function(scriptElt) {
    var script = document.createElement('script');
    script.__importElement = scriptElt;
    script.src = scriptElt.src ? scriptElt.src : 
        generateScriptDataUrl(scriptElt);
    scope.currentScript = scriptElt;
    this.trackElement(script, function(e) {
      script.parentNode.removeChild(script);
      scope.currentScript = null;  
    });
    document.head.appendChild(script);
  },
  // determine the next element in the tree which should be parsed
  nextToParse: function() {
    return !this.parsingElement && this.nextToParseInDoc(mainDoc);
  },
  nextToParseInDoc: function(doc, link) {
    var nodes = doc.querySelectorAll(this.parseSelectorsForNode(doc));
    for (var i=0, l=nodes.length, p=0, n; (i<l) && (n=nodes[i]); i++) {
      if (!this.isParsed(n)) {
        if (this.hasResource(n)) {
          return nodeIsImport(n) ? this.nextToParseInDoc(n.import, n) : n;
        } else {
          return;
        }
      }
    }
    // all nodes have been parsed, ready to parse import, if any
    return link;
  },
  // return the set of parse selectors relevant for this node.
  parseSelectorsForNode: function(node) {
    var doc = node.ownerDocument || node;
    return doc === mainDoc ? this.documentSelectors : this.importsSelectors;
  },
  isParsed: function(node) {
    return node.__importParsed;
  },
  hasResource: function(node) {
    if (nodeIsImport(node) && !node.import) {
      return false;
    }
    return true;
  }
};

function nodeIsImport(elt) {
  return (elt.localName === 'link') && (elt.rel === IMPORT_LINK_TYPE);
}

function generateScriptDataUrl(script) {
  var scriptContent = generateScriptContent(script), b64;
  try {
    b64 = btoa(scriptContent);
  } catch(e) {
    b64 = btoa(unescape(encodeURIComponent(scriptContent)));
    console.warn('Script contained non-latin characters that were forced ' +
      'to latin. Some characters may be wrong.', script);
  }
  return 'data:text/javascript;base64,' + b64;
}

function generateScriptContent(script) {
  return script.textContent + generateSourceMapHint(script);
}

// calculate source map hint
function generateSourceMapHint(script) {
  var moniker = script.__nodeUrl;
  if (!moniker) {
    moniker = script.ownerDocument.baseURI;
    // there could be more than one script this url
    var tag = '[' + Math.floor((Math.random()+1)*1000) + ']';
    // TODO(sjmiles): Polymer hack, should be pluggable if we need to allow 
    // this sort of thing
    var matches = script.textContent.match(/Polymer\(['"]([^'"]*)/);
    tag = matches && matches[1] || tag;
    // tag the moniker
    moniker += '/' + tag + '.js';
  }
  return '\n//# sourceURL=' + moniker + '\n';
}

// style/stylesheet handling

// clone style with proper path resolution for main document
// NOTE: styles are the only elements that require direct path fixup.
function cloneStyle(style) {
  var clone = style.ownerDocument.createElement('style');
  clone.textContent = style.textContent;
  path.resolveUrlsInStyle(clone);
  return clone;
}

// path fixup: style elements in imports must be made relative to the main 
// document. We fixup url's in url() and @import.
var CSS_URL_REGEXP = /(url\()([^)]*)(\))/g;
var CSS_IMPORT_REGEXP = /(@import[\s]+(?!url\())([^;]*)(;)/g;

var path = {
  resolveUrlsInStyle: function(style) {
    var doc = style.ownerDocument;
    var resolver = doc.createElement('a');
    style.textContent = this.resolveUrlsInCssText(style.textContent, resolver);
    return style;  
  },
  resolveUrlsInCssText: function(cssText, urlObj) {
    var r = this.replaceUrls(cssText, urlObj, CSS_URL_REGEXP);
    r = this.replaceUrls(r, urlObj, CSS_IMPORT_REGEXP);
    return r;
  },
  replaceUrls: function(text, urlObj, regexp) {
    return text.replace(regexp, function(m, pre, url, post) {
      var urlPath = url.replace(/["']/g, '');
      urlObj.href = urlPath;
      urlPath = urlObj.href;
      return pre + '\'' + urlPath + '\'' + post;
    });    
  }
}

// exports
scope.parser = importParser;
scope.path = path;
scope.isIE = isIe;

})(HTMLImports);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {

var hasNative = ('import' in document.createElement('link'));
var useNative = hasNative;
var flags = scope.flags;
var IMPORT_LINK_TYPE = 'import';

// TODO(sorvell): SD polyfill intrusion
var mainDoc = window.ShadowDOMPolyfill ? 
    ShadowDOMPolyfill.wrapIfNeeded(document) : document;

if (!useNative) {

  // imports
  var xhr = scope.xhr;
  var Loader = scope.Loader;
  var parser = scope.parser;

  // importer
  // highlander object to manage loading of imports

  // for any document, importer:
  // - loads any linked import documents (with deduping)

  var importer = {
    documents: {},
    // nodes to load in the mian document
    documentPreloadSelectors: 'link[rel=' + IMPORT_LINK_TYPE + ']',
    // nodes to load in imports
    importsPreloadSelectors: [
      'link[rel=' + IMPORT_LINK_TYPE + ']'
    ].join(','),
    loadNode: function(node) {
      importLoader.addNode(node);
    },
    // load all loadable elements within the parent element
    loadSubtree: function(parent) {
      var nodes = this.marshalNodes(parent);
      // add these nodes to loader's queue
      importLoader.addNodes(nodes);
    },
    marshalNodes: function(parent) {
      // all preloadable nodes in inDocument
      return parent.querySelectorAll(this.loadSelectorsForNode(parent));
    },
    // find the proper set of load selectors for a given node
    loadSelectorsForNode: function(node) {
      var doc = node.ownerDocument || node;
      return doc === mainDoc ? this.documentPreloadSelectors :
          this.importsPreloadSelectors;
    },
    loaded: function(url, elt, resource) {
      flags.load && console.log('loaded', url, elt);
      // store generic resource
      // TODO(sorvell): fails for nodes inside <template>.content
      // see https://code.google.com/p/chromium/issues/detail?id=249381.
      elt.__resource = resource;
      if (isDocumentLink(elt)) {
        var doc = this.documents[url];
        // if we've never seen a document at this url
        if (!doc) {
          // generate an HTMLDocument from data
          doc = makeDocument(resource, url);
          doc.__importLink = elt;
          // TODO(sorvell): we cannot use MO to detect parsed nodes because
          // SD polyfill does not report these as mutations.
          this.bootDocument(doc);
          // cache document
          this.documents[url] = doc;
        }
        // don't store import record until we're actually loaded
        // store document resource
        elt.import = doc;
      }
      parser.parseNext();
    },
    bootDocument: function(doc) {
      this.loadSubtree(doc);
      this.observe(doc);
      parser.parseNext();
    },
    loadedAll: function() {
      parser.parseNext();
    }
  };

  // loader singleton
  var importLoader = new Loader(importer.loaded.bind(importer), 
      importer.loadedAll.bind(importer));

  function isDocumentLink(elt) {
    return isLinkRel(elt, IMPORT_LINK_TYPE);
  }

  function isLinkRel(elt, rel) {
    return elt.localName === 'link' && elt.getAttribute('rel') === rel;
  }

  function isScript(elt) {
    return elt.localName === 'script';
  }

  function makeDocument(resource, url) {
    // create a new HTML document
    var doc = resource;
    if (!(doc instanceof Document)) {
      doc = document.implementation.createHTMLDocument(IMPORT_LINK_TYPE);
    }
    // cache the new document's source url
    doc._URL = url;
    // establish a relative path via <base>
    var base = doc.createElement('base');
    base.setAttribute('href', url);
    // add baseURI support to browsers (IE) that lack it.
    if (!doc.baseURI) {
      doc.baseURI = url;
    }
    // ensure UTF-8 charset
    var meta = doc.createElement('meta');
    meta.setAttribute('charset', 'utf-8');

    doc.head.appendChild(meta);
    doc.head.appendChild(base);
    // install HTML last as it may trigger CustomElement upgrades
    // TODO(sjmiles): problem wrt to template boostrapping below,
    // template bootstrapping must (?) come before element upgrade
    // but we cannot bootstrap templates until they are in a document
    // which is too late
    if (!(resource instanceof Document)) {
      // install html
      doc.body.innerHTML = resource;
    }
    // TODO(sorvell): ideally this code is not aware of Template polyfill,
    // but for now the polyfill needs help to bootstrap these templates
    if (window.HTMLTemplateElement && HTMLTemplateElement.bootstrap) {
      HTMLTemplateElement.bootstrap(doc);
    }
    return doc;
  }
} else {
  // do nothing if using native imports
  var importer = {};
}

// NOTE: We cannot polyfill document.currentScript because it's not possible
// both to override and maintain the ability to capture the native value;
// therefore we choose to expose _currentScript both when native imports
// and the polyfill are in use.
var currentScriptDescriptor = {
  get: function() {
    return HTMLImports.currentScript || document.currentScript;
  },
  configurable: true
};

Object.defineProperty(document, '_currentScript', currentScriptDescriptor);
Object.defineProperty(mainDoc, '_currentScript', currentScriptDescriptor);

// Polyfill document.baseURI for browsers without it.
if (!document.baseURI) {
  var baseURIDescriptor = {
    get: function() {
      return window.location.href;
    },
    configurable: true
  };

  Object.defineProperty(document, 'baseURI', baseURIDescriptor);
  Object.defineProperty(mainDoc, 'baseURI', baseURIDescriptor);
}

// call a callback when all HTMLImports in the document at call (or at least
//  document ready) time have loaded.
// 1. ensure the document is in a ready state (has dom), then 
// 2. watch for loading of imports and call callback when done
function whenImportsReady(callback, doc) {
  doc = doc || mainDoc;
  // if document is loading, wait and try again
  whenDocumentReady(function() {
    watchImportsLoad(callback, doc);
  }, doc);
}

// call the callback when the document is in a ready state (has dom)
var requiredReadyState = HTMLImports.isIE ? 'complete' : 'interactive';
var READY_EVENT = 'readystatechange';
function isDocumentReady(doc) {
  return (doc.readyState === 'complete' ||
      doc.readyState === requiredReadyState);
}

// call <callback> when we ensure the document is in a ready state
function whenDocumentReady(callback, doc) {
  if (!isDocumentReady(doc)) {
    var checkReady = function() {
      if (doc.readyState === 'complete' || 
          doc.readyState === requiredReadyState) {
        doc.removeEventListener(READY_EVENT, checkReady);
        whenDocumentReady(callback, doc);
      }
    }
    doc.addEventListener(READY_EVENT, checkReady);
  } else if (callback) {
    callback();
  }
}

// call <callback> when we ensure all imports have loaded
function watchImportsLoad(callback, doc) {
  var imports = doc.querySelectorAll('link[rel=import]');
  var loaded = 0, l = imports.length;
  function checkDone(d) { 
    if (loaded == l) {
      // go async to ensure parser isn't stuck on a script tag
      requestAnimationFrame(callback);
    }
  }
  function loadedImport(e) {
    loaded++;
    checkDone();
  }
  if (l) {
    for (var i=0, imp; (i<l) && (imp=imports[i]); i++) {
      if (isImportLoaded(imp)) {
        loadedImport.call(imp);
      } else {
        imp.addEventListener('load', loadedImport);
        imp.addEventListener('error', loadedImport);
      }
    }
  } else {
    checkDone();
  }
}

function isImportLoaded(link) {
  return useNative ? (link.import && (link.import.readyState !== 'loading')) :
      link.__importParsed;
}

// exports
scope.hasNative = hasNative;
scope.useNative = useNative;
scope.importer = importer;
scope.whenImportsReady = whenImportsReady;
scope.IMPORT_LINK_TYPE = IMPORT_LINK_TYPE;
scope.isImportLoaded = isImportLoaded;
scope.importLoader = importLoader;

})(window.HTMLImports);

 /*
Copyright 2013 The Polymer Authors. All rights reserved.
Use of this source code is governed by a BSD-style
license that can be found in the LICENSE file.
*/

(function(scope){

var IMPORT_LINK_TYPE = scope.IMPORT_LINK_TYPE;
var importSelector = 'link[rel=' + IMPORT_LINK_TYPE + ']';
var importer = scope.importer;

// we track mutations for addedNodes, looking for imports
function handler(mutations) {
  for (var i=0, l=mutations.length, m; (i<l) && (m=mutations[i]); i++) {
    if (m.type === 'childList' && m.addedNodes.length) {
      addedNodes(m.addedNodes);
    }
  }
}

// find loadable elements and add them to the importer
function addedNodes(nodes) {
  for (var i=0, l=nodes.length, n; (i<l) && (n=nodes[i]); i++) {
    if (shouldLoadNode(n)) {
      importer.loadNode(n);
    }
    if (n.children && n.children.length) {
      addedNodes(n.children);
    }
  }
}

function shouldLoadNode(node) {
  return (node.nodeType === 1) && matches.call(node,
      importer.loadSelectorsForNode(node));
}

// x-plat matches
var matches = HTMLElement.prototype.matches || 
    HTMLElement.prototype.matchesSelector || 
    HTMLElement.prototype.webkitMatchesSelector ||
    HTMLElement.prototype.mozMatchesSelector ||
    HTMLElement.prototype.msMatchesSelector;

var observer = new MutationObserver(handler);

// observe the given root for loadable elements
function observe(root) {
  observer.observe(root, {childList: true, subtree: true});
}

// exports
// TODO(sorvell): factor so can put on scope
scope.observe = observe;
importer.observe = observe;

})(HTMLImports);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */
(function(){

// bootstrap

// IE shim for CustomEvent
if (typeof window.CustomEvent !== 'function') {
  window.CustomEvent = function(inType, dictionary) {
     var e = document.createEvent('HTMLEvents');
     e.initEvent(inType,
        dictionary.bubbles === false ? false : true,
        dictionary.cancelable === false ? false : true,
        dictionary.detail);
     return e;
  };
}

// TODO(sorvell): SD polyfill intrusion
var doc = window.ShadowDOMPolyfill ? 
    window.ShadowDOMPolyfill.wrapIfNeeded(document) : document;

// Fire the 'HTMLImportsLoaded' event when imports in document at load time 
// have loaded. This event is required to simulate the script blocking 
// behavior of native imports. A main document script that needs to be sure
// imports have loaded should wait for this event.
HTMLImports.whenImportsReady(function() {
  HTMLImports.ready = true;
  HTMLImports.readyTime = new Date().getTime();
  doc.dispatchEvent(
    new CustomEvent('HTMLImportsLoaded', {bubbles: true})
  );
});


// no need to bootstrap the polyfill when native imports is available.
if (!HTMLImports.useNative) {
  function bootstrap() {
    HTMLImports.importer.bootDocument(doc);
  }
    
  // TODO(sorvell): SD polyfill does *not* generate mutations for nodes added
  // by the parser. For this reason, we must wait until the dom exists to 
  // bootstrap.
  if (document.readyState === 'complete' ||
      (document.readyState === 'interactive' && !window.attachEvent)) {
    bootstrap();
  } else {
    document.addEventListener('DOMContentLoaded', bootstrap);
  }
}

})();

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */
window.CustomElements = window.CustomElements || {flags:{}};
 /*
Copyright 2013 The Polymer Authors. All rights reserved.
Use of this source code is governed by a BSD-style
license that can be found in the LICENSE file.
*/

(function(scope){

var logFlags = window.logFlags || {};
var IMPORT_LINK_TYPE = window.HTMLImports ? HTMLImports.IMPORT_LINK_TYPE : 'none';

// walk the subtree rooted at node, applying 'find(element, data)' function
// to each element
// if 'find' returns true for 'element', do not search element's subtree
function findAll(node, find, data) {
  var e = node.firstElementChild;
  if (!e) {
    e = node.firstChild;
    while (e && e.nodeType !== Node.ELEMENT_NODE) {
      e = e.nextSibling;
    }
  }
  while (e) {
    if (find(e, data) !== true) {
      findAll(e, find, data);
    }
    e = e.nextElementSibling;
  }
  return null;
}

// walk all shadowRoots on a given node.
function forRoots(node, cb) {
  var root = node.shadowRoot;
  while(root) {
    forSubtree(root, cb);
    root = root.olderShadowRoot;
  }
}

// walk the subtree rooted at node, including descent into shadow-roots,
// applying 'cb' to each element
function forSubtree(node, cb) {
  //logFlags.dom && node.childNodes && node.childNodes.length && console.group('subTree: ', node);
  findAll(node, function(e) {
    if (cb(e)) {
      return true;
    }
    forRoots(e, cb);
  });
  forRoots(node, cb);
  //logFlags.dom && node.childNodes && node.childNodes.length && console.groupEnd();
}

// manage lifecycle on added node
function added(node) {
  if (upgrade(node)) {
    insertedNode(node);
    return true;
  }
  inserted(node);
}

// manage lifecycle on added node's subtree only
function addedSubtree(node) {
  forSubtree(node, function(e) {
    if (added(e)) {
      return true;
    }
  });
}

// manage lifecycle on added node and it's subtree
function addedNode(node) {
  return added(node) || addedSubtree(node);
}

// upgrade custom elements at node, if applicable
function upgrade(node) {
  if (!node.__upgraded__ && node.nodeType === Node.ELEMENT_NODE) {
    var type = node.getAttribute('is') || node.localName;
    var definition = scope.registry[type];
    if (definition) {
      logFlags.dom && console.group('upgrade:', node.localName);
      scope.upgrade(node);
      logFlags.dom && console.groupEnd();
      return true;
    }
  }
}

function insertedNode(node) {
  inserted(node);
  if (inDocument(node)) {
    forSubtree(node, function(e) {
      inserted(e);
    });
  }
}

// TODO(sorvell): on platforms without MutationObserver, mutations may not be
// reliable and therefore attached/detached are not reliable.
// To make these callbacks less likely to fail, we defer all inserts and removes
// to give a chance for elements to be inserted into dom.
// This ensures attachedCallback fires for elements that are created and
// immediately added to dom.
var hasPolyfillMutations = (!window.MutationObserver ||
    (window.MutationObserver === window.JsMutationObserver));
scope.hasPolyfillMutations = hasPolyfillMutations;

var isPendingMutations = false;
var pendingMutations = [];
function deferMutation(fn) {
  pendingMutations.push(fn);
  if (!isPendingMutations) {
    isPendingMutations = true;
    var async = (window.Platform && window.Platform.endOfMicrotask) ||
        setTimeout;
    async(takeMutations);
  }
}

function takeMutations() {
  isPendingMutations = false;
  var $p = pendingMutations;
  for (var i=0, l=$p.length, p; (i<l) && (p=$p[i]); i++) {
    p();
  }
  pendingMutations = [];
}

function inserted(element) {
  if (hasPolyfillMutations) {
    deferMutation(function() {
      _inserted(element);
    });
  } else {
    _inserted(element);
  }
}

// TODO(sjmiles): if there are descents into trees that can never have inDocument(*) true, fix this
function _inserted(element) {
  // TODO(sjmiles): it's possible we were inserted and removed in the space
  // of one microtask, in which case we won't be 'inDocument' here
  // But there are other cases where we are testing for inserted without
  // specific knowledge of mutations, and must test 'inDocument' to determine
  // whether to call inserted
  // If we can factor these cases into separate code paths we can have
  // better diagnostics.
  // TODO(sjmiles): when logging, do work on all custom elements so we can
  // track behavior even when callbacks not defined
  //console.log('inserted: ', element.localName);
  if (element.attachedCallback || element.detachedCallback || (element.__upgraded__ && logFlags.dom)) {
    logFlags.dom && console.group('inserted:', element.localName);
    if (inDocument(element)) {
      element.__inserted = (element.__inserted || 0) + 1;
      // if we are in a 'removed' state, bluntly adjust to an 'inserted' state
      if (element.__inserted < 1) {
        element.__inserted = 1;
      }
      // if we are 'over inserted', squelch the callback
      if (element.__inserted > 1) {
        logFlags.dom && console.warn('inserted:', element.localName,
          'insert/remove count:', element.__inserted)
      } else if (element.attachedCallback) {
        logFlags.dom && console.log('inserted:', element.localName);
        element.attachedCallback();
      }
    }
    logFlags.dom && console.groupEnd();
  }
}

function removedNode(node) {
  removed(node);
  forSubtree(node, function(e) {
    removed(e);
  });
}

function removed(element) {
  if (hasPolyfillMutations) {
    deferMutation(function() {
      _removed(element);
    });
  } else {
    _removed(element);
  }
}

function _removed(element) {
  // TODO(sjmiles): temporary: do work on all custom elements so we can track
  // behavior even when callbacks not defined
  if (element.attachedCallback || element.detachedCallback || (element.__upgraded__ && logFlags.dom)) {
    logFlags.dom && console.group('removed:', element.localName);
    if (!inDocument(element)) {
      element.__inserted = (element.__inserted || 0) - 1;
      // if we are in a 'inserted' state, bluntly adjust to an 'removed' state
      if (element.__inserted > 0) {
        element.__inserted = 0;
      }
      // if we are 'over removed', squelch the callback
      if (element.__inserted < 0) {
        logFlags.dom && console.warn('removed:', element.localName,
            'insert/remove count:', element.__inserted)
      } else if (element.detachedCallback) {
        element.detachedCallback();
      }
    }
    logFlags.dom && console.groupEnd();
  }
}

// SD polyfill intrustion due mainly to the fact that 'document'
// is not entirely wrapped
function wrapIfNeeded(node) {
  return window.ShadowDOMPolyfill ? ShadowDOMPolyfill.wrapIfNeeded(node)
      : node;
}

function inDocument(element) {
  var p = element;
  var doc = wrapIfNeeded(document);
  while (p) {
    if (p == doc) {
      return true;
    }
    p = p.parentNode || p.host;
  }
}

function watchShadow(node) {
  if (node.shadowRoot && !node.shadowRoot.__watched) {
    logFlags.dom && console.log('watching shadow-root for: ', node.localName);
    // watch all unwatched roots...
    var root = node.shadowRoot;
    while (root) {
      watchRoot(root);
      root = root.olderShadowRoot;
    }
  }
}

function watchRoot(root) {
  if (!root.__watched) {
    observe(root);
    root.__watched = true;
  }
}

function handler(mutations) {
  //
  if (logFlags.dom) {
    var mx = mutations[0];
    if (mx && mx.type === 'childList' && mx.addedNodes) {
        if (mx.addedNodes) {
          var d = mx.addedNodes[0];
          while (d && d !== document && !d.host) {
            d = d.parentNode;
          }
          var u = d && (d.URL || d._URL || (d.host && d.host.localName)) || '';
          u = u.split('/?').shift().split('/').pop();
        }
    }
    console.group('mutations (%d) [%s]', mutations.length, u || '');
  }
  //
  mutations.forEach(function(mx) {
    //logFlags.dom && console.group('mutation');
    if (mx.type === 'childList') {
      forEach(mx.addedNodes, function(n) {
        //logFlags.dom && console.log(n.localName);
        if (!n.localName) {
          return;
        }
        // nodes added may need lifecycle management
        addedNode(n);
      });
      // removed nodes may need lifecycle management
      forEach(mx.removedNodes, function(n) {
        //logFlags.dom && console.log(n.localName);
        if (!n.localName) {
          return;
        }
        removedNode(n);
      });
    }
    //logFlags.dom && console.groupEnd();
  });
  logFlags.dom && console.groupEnd();
};

var observer = new MutationObserver(handler);

function takeRecords() {
  // TODO(sjmiles): ask Raf why we have to call handler ourselves
  handler(observer.takeRecords());
  takeMutations();
}

var forEach = Array.prototype.forEach.call.bind(Array.prototype.forEach);

function observe(inRoot) {
  observer.observe(inRoot, {childList: true, subtree: true});
}

function observeDocument(doc) {
  observe(doc);
}

function upgradeDocument(doc) {
  logFlags.dom && console.group('upgradeDocument: ', (doc.baseURI).split('/').pop());
  addedNode(doc);
  logFlags.dom && console.groupEnd();
}

function upgradeDocumentTree(doc) {
  doc = wrapIfNeeded(doc);
  //console.log('upgradeDocumentTree: ', (doc.baseURI).split('/').pop());
  // upgrade contained imported documents
  var imports = doc.querySelectorAll('link[rel=' + IMPORT_LINK_TYPE + ']');
  for (var i=0, l=imports.length, n; (i<l) && (n=imports[i]); i++) {
    if (n.import && n.import.__parsed) {
      upgradeDocumentTree(n.import);
    }
  }
  upgradeDocument(doc);
}

// exports
scope.IMPORT_LINK_TYPE = IMPORT_LINK_TYPE;
scope.watchShadow = watchShadow;
scope.upgradeDocumentTree = upgradeDocumentTree;
scope.upgradeAll = addedNode;
scope.upgradeSubtree = addedSubtree;
scope.insertedNode = insertedNode;

scope.observeDocument = observeDocument;
scope.upgradeDocument = upgradeDocument;

scope.takeRecords = takeRecords;

})(window.CustomElements);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

/**
 * Implements `document.register`
 * @module CustomElements
*/

/**
 * Polyfilled extensions to the `document` object.
 * @class Document
*/

(function(scope) {

// imports

if (!scope) {
  scope = window.CustomElements = {flags:{}};
}
var flags = scope.flags;

// native document.registerElement?

var hasNative = Boolean(document.registerElement);
// TODO(sorvell): See https://github.com/Polymer/polymer/issues/399
// we'll address this by defaulting to CE polyfill in the presence of the SD
// polyfill. This will avoid spamming excess attached/detached callbacks.
// If there is a compelling need to run CE native with SD polyfill,
// we'll need to fix this issue.
var useNative = !flags.register && hasNative && !window.ShadowDOMPolyfill;

if (useNative) {

  // stub
  var nop = function() {};

  // exports
  scope.registry = {};
  scope.upgradeElement = nop;

  scope.watchShadow = nop;
  scope.upgrade = nop;
  scope.upgradeAll = nop;
  scope.upgradeSubtree = nop;
  scope.observeDocument = nop;
  scope.upgradeDocument = nop;
  scope.upgradeDocumentTree = nop;
  scope.takeRecords = nop;
  scope.reservedTagList = [];

} else {

  /**
   * Registers a custom tag name with the document.
   *
   * When a registered element is created, a `readyCallback` method is called
   * in the scope of the element. The `readyCallback` method can be specified on
   * either `options.prototype` or `options.lifecycle` with the latter taking
   * precedence.
   *
   * @method register
   * @param {String} name The tag name to register. Must include a dash ('-'),
   *    for example 'x-component'.
   * @param {Object} options
   *    @param {String} [options.extends]
   *      (_off spec_) Tag name of an element to extend (or blank for a new
   *      element). This parameter is not part of the specification, but instead
   *      is a hint for the polyfill because the extendee is difficult to infer.
   *      Remember that the input prototype must chain to the extended element's
   *      prototype (or HTMLElement.prototype) regardless of the value of
   *      `extends`.
   *    @param {Object} options.prototype The prototype to use for the new
   *      element. The prototype must inherit from HTMLElement.
   *    @param {Object} [options.lifecycle]
   *      Callbacks that fire at important phases in the life of the custom
   *      element.
   *
   * @example
   *      FancyButton = document.registerElement("fancy-button", {
   *        extends: 'button',
   *        prototype: Object.create(HTMLButtonElement.prototype, {
   *          readyCallback: {
   *            value: function() {
   *              console.log("a fancy-button was created",
   *            }
   *          }
   *        })
   *      });
   * @return {Function} Constructor for the newly registered type.
   */
  function register(name, options) {
    //console.warn('document.registerElement("' + name + '", ', options, ')');
    // construct a defintion out of options
    // TODO(sjmiles): probably should clone options instead of mutating it
    var definition = options || {};
    if (!name) {
      // TODO(sjmiles): replace with more appropriate error (EricB can probably
      // offer guidance)
      throw new Error('document.registerElement: first argument `name` must not be empty');
    }
    if (name.indexOf('-') < 0) {
      // TODO(sjmiles): replace with more appropriate error (EricB can probably
      // offer guidance)
      throw new Error('document.registerElement: first argument (\'name\') must contain a dash (\'-\'). Argument provided was \'' + String(name) + '\'.');
    }
    // prevent registering reserved names
    if (isReservedTag(name)) {
      throw new Error('Failed to execute \'registerElement\' on \'Document\': Registration failed for type \'' + String(name) + '\'. The type name is invalid.');
    }
    // elements may only be registered once
    if (getRegisteredDefinition(name)) {
      throw new Error('DuplicateDefinitionError: a type with name \'' + String(name) + '\' is already registered');
    }
    // must have a prototype, default to an extension of HTMLElement
    // TODO(sjmiles): probably should throw if no prototype, check spec
    if (!definition.prototype) {
      // TODO(sjmiles): replace with more appropriate error (EricB can probably
      // offer guidance)
      throw new Error('Options missing required prototype property');
    }
    // record name
    definition.__name = name.toLowerCase();
    // ensure a lifecycle object so we don't have to null test it
    definition.lifecycle = definition.lifecycle || {};
    // build a list of ancestral custom elements (for native base detection)
    // TODO(sjmiles): we used to need to store this, but current code only
    // uses it in 'resolveTagName': it should probably be inlined
    definition.ancestry = ancestry(definition.extends);
    // extensions of native specializations of HTMLElement require localName
    // to remain native, and use secondary 'is' specifier for extension type
    resolveTagName(definition);
    // some platforms require modifications to the user-supplied prototype
    // chain
    resolvePrototypeChain(definition);
    // overrides to implement attributeChanged callback
    overrideAttributeApi(definition.prototype);
    // 7.1.5: Register the DEFINITION with DOCUMENT
    registerDefinition(definition.__name, definition);
    // 7.1.7. Run custom element constructor generation algorithm with PROTOTYPE
    // 7.1.8. Return the output of the previous step.
    definition.ctor = generateConstructor(definition);
    definition.ctor.prototype = definition.prototype;
    // force our .constructor to be our actual constructor
    definition.prototype.constructor = definition.ctor;
    // if initial parsing is complete
    if (scope.ready) {
      // upgrade any pre-existing nodes of this type
      scope.upgradeDocumentTree(document);
    }
    return definition.ctor;
  }

  function isReservedTag(name) {
    for (var i = 0; i < reservedTagList.length; i++) {
      if (name === reservedTagList[i]) {
        return true;
      }
    }
  }

  var reservedTagList = [
    'annotation-xml', 'color-profile', 'font-face', 'font-face-src',
    'font-face-uri', 'font-face-format', 'font-face-name', 'missing-glyph'
  ];

  function ancestry(extnds) {
    var extendee = getRegisteredDefinition(extnds);
    if (extendee) {
      return ancestry(extendee.extends).concat([extendee]);
    }
    return [];
  }

  function resolveTagName(definition) {
    // if we are explicitly extending something, that thing is our
    // baseTag, unless it represents a custom component
    var baseTag = definition.extends;
    // if our ancestry includes custom components, we only have a
    // baseTag if one of them does
    for (var i=0, a; (a=definition.ancestry[i]); i++) {
      baseTag = a.is && a.tag;
    }
    // our tag is our baseTag, if it exists, and otherwise just our name
    definition.tag = baseTag || definition.__name;
    if (baseTag) {
      // if there is a base tag, use secondary 'is' specifier
      definition.is = definition.__name;
    }
  }

  function resolvePrototypeChain(definition) {
    // if we don't support __proto__ we need to locate the native level
    // prototype for precise mixing in
    if (!Object.__proto__) {
      // default prototype
      var nativePrototype = HTMLElement.prototype;
      // work out prototype when using type-extension
      if (definition.is) {
        var inst = document.createElement(definition.tag);
        nativePrototype = Object.getPrototypeOf(inst);
      }
      // ensure __proto__ reference is installed at each point on the prototype
      // chain.
      // NOTE: On platforms without __proto__, a mixin strategy is used instead
      // of prototype swizzling. In this case, this generated __proto__ provides
      // limited support for prototype traversal.
      var proto = definition.prototype, ancestor;
      while (proto && (proto !== nativePrototype)) {
        var ancestor = Object.getPrototypeOf(proto);
        proto.__proto__ = ancestor;
        proto = ancestor;
      }
    }
    // cache this in case of mixin
    definition.native = nativePrototype;
  }

  // SECTION 4

  function instantiate(definition) {
    // 4.a.1. Create a new object that implements PROTOTYPE
    // 4.a.2. Let ELEMENT by this new object
    //
    // the custom element instantiation algorithm must also ensure that the
    // output is a valid DOM element with the proper wrapper in place.
    //
    return upgrade(domCreateElement(definition.tag), definition);
  }

  function upgrade(element, definition) {
    // some definitions specify an 'is' attribute
    if (definition.is) {
      element.setAttribute('is', definition.is);
    }
    // remove 'unresolved' attr, which is a standin for :unresolved.
    element.removeAttribute('unresolved');
    // make 'element' implement definition.prototype
    implement(element, definition);
    // flag as upgraded
    element.__upgraded__ = true;
    // lifecycle management
    created(element);
    // attachedCallback fires in tree order, call before recursing
    scope.insertedNode(element);
    // there should never be a shadow root on element at this point
    scope.upgradeSubtree(element);
    // OUTPUT
    return element;
  }

  function implement(element, definition) {
    // prototype swizzling is best
    if (Object.__proto__) {
      element.__proto__ = definition.prototype;
    } else {
      // where above we can re-acquire inPrototype via
      // getPrototypeOf(Element), we cannot do so when
      // we use mixin, so we install a magic reference
      customMixin(element, definition.prototype, definition.native);
      element.__proto__ = definition.prototype;
    }
  }

  function customMixin(inTarget, inSrc, inNative) {
    // TODO(sjmiles): 'used' allows us to only copy the 'youngest' version of
    // any property. This set should be precalculated. We also need to
    // consider this for supporting 'super'.
    var used = {};
    // start with inSrc
    var p = inSrc;
    // The default is HTMLElement.prototype, so we add a test to avoid mixing in
    // native prototypes
    while (p !== inNative && p !== HTMLElement.prototype) {
      var keys = Object.getOwnPropertyNames(p);
      for (var i=0, k; k=keys[i]; i++) {
        if (!used[k]) {
          Object.defineProperty(inTarget, k,
              Object.getOwnPropertyDescriptor(p, k));
          used[k] = 1;
        }
      }
      p = Object.getPrototypeOf(p);
    }
  }

  function created(element) {
    // invoke createdCallback
    if (element.createdCallback) {
      element.createdCallback();
    }
  }

  // attribute watching

  function overrideAttributeApi(prototype) {
    // overrides to implement callbacks
    // TODO(sjmiles): should support access via .attributes NamedNodeMap
    // TODO(sjmiles): preserves user defined overrides, if any
    if (prototype.setAttribute._polyfilled) {
      return;
    }
    var setAttribute = prototype.setAttribute;
    prototype.setAttribute = function(name, value) {
      changeAttribute.call(this, name, value, setAttribute);
    }
    var removeAttribute = prototype.removeAttribute;
    prototype.removeAttribute = function(name) {
      changeAttribute.call(this, name, null, removeAttribute);
    }
    prototype.setAttribute._polyfilled = true;
  }

  // https://dvcs.w3.org/hg/webcomponents/raw-file/tip/spec/custom/
  // index.html#dfn-attribute-changed-callback
  function changeAttribute(name, value, operation) {
    var oldValue = this.getAttribute(name);
    operation.apply(this, arguments);
    var newValue = this.getAttribute(name);
    if (this.attributeChangedCallback
        && (newValue !== oldValue)) {
      this.attributeChangedCallback(name, oldValue, newValue);
    }
  }

  // element registry (maps tag names to definitions)

  var registry = {};

  function getRegisteredDefinition(name) {
    if (name) {
      return registry[name.toLowerCase()];
    }
  }

  function registerDefinition(name, definition) {
    registry[name] = definition;
  }

  function generateConstructor(definition) {
    return function() {
      return instantiate(definition);
    };
  }

  var HTML_NAMESPACE = 'http://www.w3.org/1999/xhtml';
  function createElementNS(namespace, tag, typeExtension) {
    // NOTE: we do not support non-HTML elements,
    // just call createElementNS for non HTML Elements
    if (namespace === HTML_NAMESPACE) {
      return createElement(tag, typeExtension);
    } else {
      return domCreateElementNS(namespace, tag);
    }
  }

  function createElement(tag, typeExtension) {
    // TODO(sjmiles): ignore 'tag' when using 'typeExtension', we could
    // error check it, or perhaps there should only ever be one argument
    var definition = getRegisteredDefinition(typeExtension || tag);
    if (definition) {
      if (tag == definition.tag && typeExtension == definition.is) {
        return new definition.ctor();
      }
      // Handle empty string for type extension.
      if (!typeExtension && !definition.is) {
        return new definition.ctor();
      }
    }

    if (typeExtension) {
      var element = createElement(tag);
      element.setAttribute('is', typeExtension);
      return element;
    }
    var element = domCreateElement(tag);
    // Custom tags should be HTMLElements even if not upgraded.
    if (tag.indexOf('-') >= 0) {
      implement(element, HTMLElement);
    }
    return element;
  }

  function upgradeElement(element) {
    if (!element.__upgraded__ && (element.nodeType === Node.ELEMENT_NODE)) {
      var is = element.getAttribute('is');
      var definition = getRegisteredDefinition(is || element.localName);
      if (definition) {
        if (is && definition.tag == element.localName) {
          return upgrade(element, definition);
        } else if (!is && !definition.extends) {
          return upgrade(element, definition);
        }
      }
    }
  }

  function cloneNode(deep) {
    // call original clone
    var n = domCloneNode.call(this, deep);
    // upgrade the element and subtree
    scope.upgradeAll(n);
    // return the clone
    return n;
  }
  // capture native createElement before we override it

  var domCreateElement = document.createElement.bind(document);
  var domCreateElementNS = document.createElementNS.bind(document);

  // capture native cloneNode before we override it

  var domCloneNode = Node.prototype.cloneNode;

  // exports

  document.registerElement = register;
  document.createElement = createElement; // override
  document.createElementNS = createElementNS; // override
  Node.prototype.cloneNode = cloneNode; // override

  scope.registry = registry;

  /**
   * Upgrade an element to a custom element. Upgrading an element
   * causes the custom prototype to be applied, an `is` attribute
   * to be attached (as needed), and invocation of the `readyCallback`.
   * `upgrade` does nothing if the element is already upgraded, or
   * if it matches no registered custom tag name.
   *
   * @method ugprade
   * @param {Element} element The element to upgrade.
   * @return {Element} The upgraded element.
   */
  scope.upgrade = upgradeElement;
}

// Create a custom 'instanceof'. This is necessary when CustomElements
// are implemented via a mixin strategy, as for example on IE10.
var isInstance;
if (!Object.__proto__ && !useNative) {
  isInstance = function(obj, ctor) {
    var p = obj;
    while (p) {
      // NOTE: this is not technically correct since we're not checking if
      // an object is an instance of a constructor; however, this should
      // be good enough for the mixin strategy.
      if (p === ctor.prototype) {
        return true;
      }
      p = p.__proto__;
    }
    return false;
  }
} else {
  isInstance = function(obj, base) {
    return obj instanceof base;
  }
}

// exports
scope.instanceof = isInstance;
scope.reservedTagList = reservedTagList;

// bc
document.register = document.registerElement;

scope.hasNative = hasNative;
scope.useNative = useNative;

})(window.CustomElements);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {

// import

var IMPORT_LINK_TYPE = scope.IMPORT_LINK_TYPE;

// highlander object for parsing a document tree

var parser = {
  selectors: [
    'link[rel=' + IMPORT_LINK_TYPE + ']'
  ],
  map: {
    link: 'parseLink'
  },
  parse: function(inDocument) {
    if (!inDocument.__parsed) {
      // only parse once
      inDocument.__parsed = true;
      // all parsable elements in inDocument (depth-first pre-order traversal)
      var elts = inDocument.querySelectorAll(parser.selectors);
      // for each parsable node type, call the mapped parsing method
      forEach(elts, function(e) {
        parser[parser.map[e.localName]](e);
      });
      // upgrade all upgradeable static elements, anything dynamically
      // created should be caught by observer
      CustomElements.upgradeDocument(inDocument);
      // observe document for dom changes
      CustomElements.observeDocument(inDocument);
    }
  },
  parseLink: function(linkElt) {
    // imports
    if (isDocumentLink(linkElt)) {
      this.parseImport(linkElt);
    }
  },
  parseImport: function(linkElt) {
    if (linkElt.import) {
      parser.parse(linkElt.import);
    }
  }
};

function isDocumentLink(inElt) {
  return (inElt.localName === 'link'
      && inElt.getAttribute('rel') === IMPORT_LINK_TYPE);
}

var forEach = Array.prototype.forEach.call.bind(Array.prototype.forEach);

// exports

scope.parser = parser;
scope.IMPORT_LINK_TYPE = IMPORT_LINK_TYPE;

})(window.CustomElements);
/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */
(function(scope){

// bootstrap parsing
function bootstrap() {
  // parse document
  CustomElements.parser.parse(document);
  // one more pass before register is 'live'
  CustomElements.upgradeDocument(document);
  // choose async
  var async = window.Platform && Platform.endOfMicrotask ? 
    Platform.endOfMicrotask :
    setTimeout;
  async(function() {
    // set internal 'ready' flag, now document.registerElement will trigger 
    // synchronous upgrades
    CustomElements.ready = true;
    // capture blunt profiling data
    CustomElements.readyTime = Date.now();
    if (window.HTMLImports) {
      CustomElements.elapsed = CustomElements.readyTime - HTMLImports.readyTime;
    }
    // notify the system that we are bootstrapped
    document.dispatchEvent(
      new CustomEvent('WebComponentsReady', {bubbles: true})
    );

    // install upgrade hook if HTMLImports are available
    if (window.HTMLImports) {
      HTMLImports.__importsParsingHook = function(elt) {
        CustomElements.parser.parse(elt.import);
      }
    }
  });
}

// CustomEvent shim for IE
if (typeof window.CustomEvent !== 'function') {
  window.CustomEvent = function(inType) {
    var e = document.createEvent('HTMLEvents');
    e.initEvent(inType, true, true);
    return e;
  };
}

// When loading at readyState complete time (or via flag), boot custom elements
// immediately.
// If relevant, HTMLImports must already be loaded.
if (document.readyState === 'complete' || scope.flags.eager) {
  bootstrap();
// When loading at readyState interactive time, bootstrap only if HTMLImports
// are not pending. Also avoid IE as the semantics of this state are unreliable.
} else if (document.readyState === 'interactive' && !window.attachEvent &&
    (!window.HTMLImports || window.HTMLImports.ready)) {
  bootstrap();
// When loading at other readyStates, wait for the appropriate DOM event to 
// bootstrap.
} else {
  var loadEvent = window.HTMLImports && !HTMLImports.ready ?
      'HTMLImportsLoaded' : 'DOMContentLoaded';
  window.addEventListener(loadEvent, bootstrap);
}

})(window.CustomElements);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */
(function() {

if (window.ShadowDOMPolyfill) {

  // ensure wrapped inputs for these functions
  var fns = ['upgradeAll', 'upgradeSubtree', 'observeDocument',
      'upgradeDocument'];

  // cache originals
  var original = {};
  fns.forEach(function(fn) {
    original[fn] = CustomElements[fn];
  });

  // override
  fns.forEach(function(fn) {
    CustomElements[fn] = function(inNode) {
      return original[fn](wrap(inNode));
    };
  });

}

})();

/*
 * Copyright 2014 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */
(function(scope) {
  var endOfMicrotask = scope.endOfMicrotask;

  // Generic url loader
  function Loader(regex) {
    this.regex = regex;
  }
  Loader.prototype = {
    // TODO(dfreedm): there may be a better factoring here
    // extract absolute urls from the text (full of relative urls)
    extractUrls: function(text, base) {
      var matches = [];
      var matched, u;
      while ((matched = this.regex.exec(text))) {
        u = new URL(matched[1], base);
        matches.push({matched: matched[0], url: u.href});
      }
      return matches;
    },
    // take a text blob, a root url, and a callback and load all the urls found within the text
    // returns a map of absolute url to text
    process: function(text, root, callback) {
      var matches = this.extractUrls(text, root);
      this.fetch(matches, {}, callback);
    },
    // build a mapping of url -> text from matches
    fetch: function(matches, map, callback) {
      var inflight = matches.length;

      // return early if there is no fetching to be done
      if (!inflight) {
        return callback(map);
      }

      var done = function() {
        if (--inflight === 0) {
          callback(map);
        }
      };

      // map url -> responseText
      var handleXhr = function(err, request) {
        var match = request.match;
        var key = match.url;
        // handle errors with an empty string
        if (err) {
          map[key] = '';
          return done();
        }
        var response = request.response || request.responseText;
        map[key] = response;
        this.fetch(this.extractUrls(response, key), map, done);
      };

      var m, req, url;
      for (var i = 0; i < inflight; i++) {
        m = matches[i];
        url = m.url;
        // if this url has already been requested, skip requesting it again
        if (map[url]) {
          // Async call to done to simplify the inflight logic
          endOfMicrotask(done);
          continue;
        }
        req = this.xhr(url, handleXhr, this);
        req.match = m;
        // tag the map with an XHR request to deduplicate at the same level
        map[url] = req;
      }
    },
    xhr: function(url, callback, scope) {
      var request = new XMLHttpRequest();
      request.open('GET', url, true);
      request.send();
      request.onload = function() {
        callback.call(scope, null, request);
      };
      request.onerror = function() {
        callback.call(scope, null, request);
      };
      return request;
    }
  };

  scope.Loader = Loader;
})(window.Platform);

/*
 * Copyright 2014 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */
(function(scope) {

var urlResolver = scope.urlResolver;
var Loader = scope.Loader;

function StyleResolver() {
  this.loader = new Loader(this.regex);
}
StyleResolver.prototype = {
  regex: /@import\s+(?:url)?["'\(]*([^'"\)]*)['"\)]*;/g,
  // Recursively replace @imports with the text at that url
  resolve: function(text, url, callback) {
    var done = function(map) {
      callback(this.flatten(text, url, map));
    }.bind(this);
    this.loader.process(text, url, done);
  },
  // resolve the textContent of a style node
  resolveNode: function(style, callback) {
    var text = style.textContent;
    var url = style.ownerDocument.baseURI;
    var done = function(text) {
      style.textContent = text;
      callback(style);
    };
    this.resolve(text, url, done);
  },
  // flatten all the @imports to text
  flatten: function(text, base, map) {
    var matches = this.loader.extractUrls(text, base);
    var match, url, intermediate;
    for (var i = 0; i < matches.length; i++) {
      match = matches[i];
      url = match.url;
      // resolve any css text to be relative to the importer
      intermediate = urlResolver.resolveCssText(map[url], url);
      // flatten intermediate @imports
      intermediate = this.flatten(intermediate, url, map);
      text = text.replace(match.matched, intermediate);
    }
    return text;
  },
  loadStyles: function(styles, callback) {
    var loaded=0, l = styles.length;
    // called in the context of the style
    function loadedStyle(style) {
      loaded++;
      if (loaded === l && callback) {
        callback();
      }
    }
    for (var i=0, s; (i<l) && (s=styles[i]); i++) {
      this.resolveNode(s, loadedStyle);
    }
  }
};

var styleResolver = new StyleResolver();

// exports
scope.styleResolver = styleResolver;

})(window.Platform);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {
  scope = scope || {};
  scope.external = scope.external || {};
  var target = {
    shadow: function(inEl) {
      if (inEl) {
        return inEl.shadowRoot || inEl.webkitShadowRoot;
      }
    },
    canTarget: function(shadow) {
      return shadow && Boolean(shadow.elementFromPoint);
    },
    targetingShadow: function(inEl) {
      var s = this.shadow(inEl);
      if (this.canTarget(s)) {
        return s;
      }
    },
    olderShadow: function(shadow) {
      var os = shadow.olderShadowRoot;
      if (!os) {
        var se = shadow.querySelector('shadow');
        if (se) {
          os = se.olderShadowRoot;
        }
      }
      return os;
    },
    allShadows: function(element) {
      var shadows = [], s = this.shadow(element);
      while(s) {
        shadows.push(s);
        s = this.olderShadow(s);
      }
      return shadows;
    },
    searchRoot: function(inRoot, x, y) {
      if (inRoot) {
        var t = inRoot.elementFromPoint(x, y);
        var st, sr, os;
        // is element a shadow host?
        sr = this.targetingShadow(t);
        while (sr) {
          // find the the element inside the shadow root
          st = sr.elementFromPoint(x, y);
          if (!st) {
            // check for older shadows
            sr = this.olderShadow(sr);
          } else {
            // shadowed element may contain a shadow root
            var ssr = this.targetingShadow(st);
            return this.searchRoot(ssr, x, y) || st;
          }
        }
        // light dom element is the target
        return t;
      }
    },
    owner: function(element) {
      var s = element;
      // walk up until you hit the shadow root or document
      while (s.parentNode) {
        s = s.parentNode;
      }
      // the owner element is expected to be a Document or ShadowRoot
      if (s.nodeType != Node.DOCUMENT_NODE && s.nodeType != Node.DOCUMENT_FRAGMENT_NODE) {
        s = document;
      }
      return s;
    },
    findTarget: function(inEvent) {
      var x = inEvent.clientX, y = inEvent.clientY;
      // if the listener is in the shadow root, it is much faster to start there
      var s = this.owner(inEvent.target);
      // if x, y is not in this root, fall back to document search
      if (!s.elementFromPoint(x, y)) {
        s = document;
      }
      return this.searchRoot(s, x, y);
    }
  };
  scope.targetFinding = target;
  scope.findTarget = target.findTarget.bind(target);

  window.PointerEventsPolyfill = scope;
})(window.PointerEventsPolyfill);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */
(function() {
  function shadowSelector(v) {
    return 'body /shadow-deep/ ' + selector(v);
  }
  function selector(v) {
    return '[touch-action="' + v + '"]';
  }
  function rule(v) {
    return '{ -ms-touch-action: ' + v + '; touch-action: ' + v + '; touch-action-delay: none; }';
  }
  var attrib2css = [
    'none',
    'auto',
    'pan-x',
    'pan-y',
    {
      rule: 'pan-x pan-y',
      selectors: [
        'pan-x pan-y',
        'pan-y pan-x'
      ]
    }
  ];
  var styles = '';
  // only install stylesheet if the browser has touch action support
  var head = document.head;
  var hasNativePE = window.PointerEvent || window.MSPointerEvent;
  // only add shadow selectors if shadowdom is supported
  var hasShadowRoot = !window.ShadowDOMPolyfill && document.head.createShadowRoot;

  if (hasNativePE) {
    attrib2css.forEach(function(r) {
      if (String(r) === r) {
        styles += selector(r) + rule(r) + '\n';
        if (hasShadowRoot) {
          styles += shadowSelector(r) + rule(r) + '\n';
        }
      } else {
        styles += r.selectors.map(selector) + rule(r.rule) + '\n';
        if (hasShadowRoot) {
          styles += r.selectors.map(shadowSelector) + rule(r.rule) + '\n';
        }
      }
    });

    var el = document.createElement('style');
    el.textContent = styles;
    document.head.appendChild(el);
  }
})();

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

/**
 * This is the constructor for new PointerEvents.
 *
 * New Pointer Events must be given a type, and an optional dictionary of
 * initialization properties.
 *
 * Due to certain platform requirements, events returned from the constructor
 * identify as MouseEvents.
 *
 * @constructor
 * @param {String} inType The type of the event to create.
 * @param {Object} [inDict] An optional dictionary of initial event properties.
 * @return {Event} A new PointerEvent of type `inType` and initialized with properties from `inDict`.
 */
(function(scope) {

  var MOUSE_PROPS = [
    'bubbles',
    'cancelable',
    'view',
    'detail',
    'screenX',
    'screenY',
    'clientX',
    'clientY',
    'ctrlKey',
    'altKey',
    'shiftKey',
    'metaKey',
    'button',
    'relatedTarget',
    'pageX',
    'pageY'
  ];

  var MOUSE_DEFAULTS = [
    false,
    false,
    null,
    null,
    0,
    0,
    0,
    0,
    false,
    false,
    false,
    false,
    0,
    null,
    0,
    0
  ];

  function PointerEvent(inType, inDict) {
    inDict = inDict || Object.create(null);

    var e = document.createEvent('Event');
    e.initEvent(inType, inDict.bubbles || false, inDict.cancelable || false);

    // define inherited MouseEvent properties
    for(var i = 0, p; i < MOUSE_PROPS.length; i++) {
      p = MOUSE_PROPS[i];
      e[p] = inDict[p] || MOUSE_DEFAULTS[i];
    }
    e.buttons = inDict.buttons || 0;

    // Spec requires that pointers without pressure specified use 0.5 for down
    // state and 0 for up state.
    var pressure = 0;
    if (inDict.pressure) {
      pressure = inDict.pressure;
    } else {
      pressure = e.buttons ? 0.5 : 0;
    }

    // add x/y properties aliased to clientX/Y
    e.x = e.clientX;
    e.y = e.clientY;

    // define the properties of the PointerEvent interface
    e.pointerId = inDict.pointerId || 0;
    e.width = inDict.width || 0;
    e.height = inDict.height || 0;
    e.pressure = pressure;
    e.tiltX = inDict.tiltX || 0;
    e.tiltY = inDict.tiltY || 0;
    e.pointerType = inDict.pointerType || '';
    e.hwTimestamp = inDict.hwTimestamp || 0;
    e.isPrimary = inDict.isPrimary || false;
    return e;
  }

  // attach to window
  if (!scope.PointerEvent) {
    scope.PointerEvent = PointerEvent;
  }
})(window);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

/**
 * This module implements an map of pointer states
 */
(function(scope) {
  var USE_MAP = window.Map && window.Map.prototype.forEach;
  var POINTERS_FN = function(){ return this.size; };
  function PointerMap() {
    if (USE_MAP) {
      var m = new Map();
      m.pointers = POINTERS_FN;
      return m;
    } else {
      this.keys = [];
      this.values = [];
    }
  }

  PointerMap.prototype = {
    set: function(inId, inEvent) {
      var i = this.keys.indexOf(inId);
      if (i > -1) {
        this.values[i] = inEvent;
      } else {
        this.keys.push(inId);
        this.values.push(inEvent);
      }
    },
    has: function(inId) {
      return this.keys.indexOf(inId) > -1;
    },
    'delete': function(inId) {
      var i = this.keys.indexOf(inId);
      if (i > -1) {
        this.keys.splice(i, 1);
        this.values.splice(i, 1);
      }
    },
    get: function(inId) {
      var i = this.keys.indexOf(inId);
      return this.values[i];
    },
    clear: function() {
      this.keys.length = 0;
      this.values.length = 0;
    },
    // return value, key, map
    forEach: function(callback, thisArg) {
      this.values.forEach(function(v, i) {
        callback.call(thisArg, v, this.keys[i], this);
      }, this);
    },
    pointers: function() {
      return this.keys.length;
    }
  };

  scope.PointerMap = PointerMap;
})(window.PointerEventsPolyfill);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {
  var CLONE_PROPS = [
    // MouseEvent
    'bubbles',
    'cancelable',
    'view',
    'detail',
    'screenX',
    'screenY',
    'clientX',
    'clientY',
    'ctrlKey',
    'altKey',
    'shiftKey',
    'metaKey',
    'button',
    'relatedTarget',
    // DOM Level 3
    'buttons',
    // PointerEvent
    'pointerId',
    'width',
    'height',
    'pressure',
    'tiltX',
    'tiltY',
    'pointerType',
    'hwTimestamp',
    'isPrimary',
    // event instance
    'type',
    'target',
    'currentTarget',
    'which',
    'pageX',
    'pageY'
  ];

  var CLONE_DEFAULTS = [
    // MouseEvent
    false,
    false,
    null,
    null,
    0,
    0,
    0,
    0,
    false,
    false,
    false,
    false,
    0,
    null,
    // DOM Level 3
    0,
    // PointerEvent
    0,
    0,
    0,
    0,
    0,
    0,
    '',
    0,
    false,
    // event instance
    '',
    null,
    null,
    0,
    0,
    0
  ];

  var HAS_SVG_INSTANCE = (typeof SVGElementInstance !== 'undefined');

  /**
   * This module is for normalizing events. Mouse and Touch events will be
   * collected here, and fire PointerEvents that have the same semantics, no
   * matter the source.
   * Events fired:
   *   - pointerdown: a pointing is added
   *   - pointerup: a pointer is removed
   *   - pointermove: a pointer is moved
   *   - pointerover: a pointer crosses into an element
   *   - pointerout: a pointer leaves an element
   *   - pointercancel: a pointer will no longer generate events
   */
  var dispatcher = {
    pointermap: new scope.PointerMap(),
    eventMap: Object.create(null),
    captureInfo: Object.create(null),
    // Scope objects for native events.
    // This exists for ease of testing.
    eventSources: Object.create(null),
    eventSourceList: [],
    /**
     * Add a new event source that will generate pointer events.
     *
     * `inSource` must contain an array of event names named `events`, and
     * functions with the names specified in the `events` array.
     * @param {string} name A name for the event source
     * @param {Object} source A new source of platform events.
     */
    registerSource: function(name, source) {
      var s = source;
      var newEvents = s.events;
      if (newEvents) {
        newEvents.forEach(function(e) {
          if (s[e]) {
            this.eventMap[e] = s[e].bind(s);
          }
        }, this);
        this.eventSources[name] = s;
        this.eventSourceList.push(s);
      }
    },
    register: function(element) {
      var l = this.eventSourceList.length;
      for (var i = 0, es; (i < l) && (es = this.eventSourceList[i]); i++) {
        // call eventsource register
        es.register.call(es, element);
      }
    },
    unregister: function(element) {
      var l = this.eventSourceList.length;
      for (var i = 0, es; (i < l) && (es = this.eventSourceList[i]); i++) {
        // call eventsource register
        es.unregister.call(es, element);
      }
    },
    contains: scope.external.contains || function(container, contained) {
      return container.contains(contained);
    },
    // EVENTS
    down: function(inEvent) {
      inEvent.bubbles = true;
      this.fireEvent('pointerdown', inEvent);
    },
    move: function(inEvent) {
      inEvent.bubbles = true;
      this.fireEvent('pointermove', inEvent);
    },
    up: function(inEvent) {
      inEvent.bubbles = true;
      this.fireEvent('pointerup', inEvent);
    },
    enter: function(inEvent) {
      inEvent.bubbles = false;
      this.fireEvent('pointerenter', inEvent);
    },
    leave: function(inEvent) {
      inEvent.bubbles = false;
      this.fireEvent('pointerleave', inEvent);
    },
    over: function(inEvent) {
      inEvent.bubbles = true;
      this.fireEvent('pointerover', inEvent);
    },
    out: function(inEvent) {
      inEvent.bubbles = true;
      this.fireEvent('pointerout', inEvent);
    },
    cancel: function(inEvent) {
      inEvent.bubbles = true;
      this.fireEvent('pointercancel', inEvent);
    },
    leaveOut: function(event) {
      this.out(event);
      if (!this.contains(event.target, event.relatedTarget)) {
        this.leave(event);
      }
    },
    enterOver: function(event) {
      this.over(event);
      if (!this.contains(event.target, event.relatedTarget)) {
        this.enter(event);
      }
    },
    // LISTENER LOGIC
    eventHandler: function(inEvent) {
      // This is used to prevent multiple dispatch of pointerevents from
      // platform events. This can happen when two elements in different scopes
      // are set up to create pointer events, which is relevant to Shadow DOM.
      if (inEvent._handledByPE) {
        return;
      }
      var type = inEvent.type;
      var fn = this.eventMap && this.eventMap[type];
      if (fn) {
        fn(inEvent);
      }
      inEvent._handledByPE = true;
    },
    // set up event listeners
    listen: function(target, events) {
      events.forEach(function(e) {
        this.addEvent(target, e);
      }, this);
    },
    // remove event listeners
    unlisten: function(target, events) {
      events.forEach(function(e) {
        this.removeEvent(target, e);
      }, this);
    },
    addEvent: scope.external.addEvent || function(target, eventName) {
      target.addEventListener(eventName, this.boundHandler);
    },
    removeEvent: scope.external.removeEvent || function(target, eventName) {
      target.removeEventListener(eventName, this.boundHandler);
    },
    // EVENT CREATION AND TRACKING
    /**
     * Creates a new Event of type `inType`, based on the information in
     * `inEvent`.
     *
     * @param {string} inType A string representing the type of event to create
     * @param {Event} inEvent A platform event with a target
     * @return {Event} A PointerEvent of type `inType`
     */
    makeEvent: function(inType, inEvent) {
      // relatedTarget must be null if pointer is captured
      if (this.captureInfo[inEvent.pointerId]) {
        inEvent.relatedTarget = null;
      }
      var e = new PointerEvent(inType, inEvent);
      if (inEvent.preventDefault) {
        e.preventDefault = inEvent.preventDefault;
      }
      e._target = e._target || inEvent.target;
      return e;
    },
    // make and dispatch an event in one call
    fireEvent: function(inType, inEvent) {
      var e = this.makeEvent(inType, inEvent);
      return this.dispatchEvent(e);
    },
    /**
     * Returns a snapshot of inEvent, with writable properties.
     *
     * @param {Event} inEvent An event that contains properties to copy.
     * @return {Object} An object containing shallow copies of `inEvent`'s
     *    properties.
     */
    cloneEvent: function(inEvent) {
      var eventCopy = Object.create(null), p;
      for (var i = 0; i < CLONE_PROPS.length; i++) {
        p = CLONE_PROPS[i];
        eventCopy[p] = inEvent[p] || CLONE_DEFAULTS[i];
        // Work around SVGInstanceElement shadow tree
        // Return the <use> element that is represented by the instance for Safari, Chrome, IE.
        // This is the behavior implemented by Firefox.
        if (HAS_SVG_INSTANCE && (p === 'target' || p === 'relatedTarget')) {
          if (eventCopy[p] instanceof SVGElementInstance) {
            eventCopy[p] = eventCopy[p].correspondingUseElement;
          }
        }
      }
      // keep the semantics of preventDefault
      if (inEvent.preventDefault) {
        eventCopy.preventDefault = function() {
          inEvent.preventDefault();
        };
      }
      return eventCopy;
    },
    getTarget: function(inEvent) {
      // if pointer capture is set, route all events for the specified pointerId
      // to the capture target
      return this.captureInfo[inEvent.pointerId] || inEvent._target;
    },
    setCapture: function(inPointerId, inTarget) {
      if (this.captureInfo[inPointerId]) {
        this.releaseCapture(inPointerId);
      }
      this.captureInfo[inPointerId] = inTarget;
      var e = document.createEvent('Event');
      e.initEvent('gotpointercapture', true, false);
      e.pointerId = inPointerId;
      this.implicitRelease = this.releaseCapture.bind(this, inPointerId);
      document.addEventListener('pointerup', this.implicitRelease);
      document.addEventListener('pointercancel', this.implicitRelease);
      e._target = inTarget;
      this.asyncDispatchEvent(e);
    },
    releaseCapture: function(inPointerId) {
      var t = this.captureInfo[inPointerId];
      if (t) {
        var e = document.createEvent('Event');
        e.initEvent('lostpointercapture', true, false);
        e.pointerId = inPointerId;
        this.captureInfo[inPointerId] = undefined;
        document.removeEventListener('pointerup', this.implicitRelease);
        document.removeEventListener('pointercancel', this.implicitRelease);
        e._target = t;
        this.asyncDispatchEvent(e);
      }
    },
    /**
     * Dispatches the event to its target.
     *
     * @param {Event} inEvent The event to be dispatched.
     * @return {Boolean} True if an event handler returns true, false otherwise.
     */
    dispatchEvent: scope.external.dispatchEvent || function(inEvent) {
      var t = this.getTarget(inEvent);
      if (t) {
        return t.dispatchEvent(inEvent);
      }
    },
    asyncDispatchEvent: function(inEvent) {
      requestAnimationFrame(this.dispatchEvent.bind(this, inEvent));
    }
  };
  dispatcher.boundHandler = dispatcher.eventHandler.bind(dispatcher);
  scope.dispatcher = dispatcher;
  scope.register = dispatcher.register.bind(dispatcher);
  scope.unregister = dispatcher.unregister.bind(dispatcher);
})(window.PointerEventsPolyfill);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

/**
 * This module uses Mutation Observers to dynamically adjust which nodes will
 * generate Pointer Events.
 *
 * All nodes that wish to generate Pointer Events must have the attribute
 * `touch-action` set to `none`.
 */
(function(scope) {
  var forEach = Array.prototype.forEach.call.bind(Array.prototype.forEach);
  var map = Array.prototype.map.call.bind(Array.prototype.map);
  var toArray = Array.prototype.slice.call.bind(Array.prototype.slice);
  var filter = Array.prototype.filter.call.bind(Array.prototype.filter);
  var MO = window.MutationObserver || window.WebKitMutationObserver;
  var SELECTOR = '[touch-action]';
  var OBSERVER_INIT = {
    subtree: true,
    childList: true,
    attributes: true,
    attributeOldValue: true,
    attributeFilter: ['touch-action']
  };

  function Installer(add, remove, changed, binder) {
    this.addCallback = add.bind(binder);
    this.removeCallback = remove.bind(binder);
    this.changedCallback = changed.bind(binder);
    if (MO) {
      this.observer = new MO(this.mutationWatcher.bind(this));
    }
  }

  Installer.prototype = {
    watchSubtree: function(target) {
      // Only watch scopes that can target find, as these are top-level.
      // Otherwise we can see duplicate additions and removals that add noise.
      //
      // TODO(dfreedman): For some instances with ShadowDOMPolyfill, we can see
      // a removal without an insertion when a node is redistributed among
      // shadows. Since it all ends up correct in the document, watching only
      // the document will yield the correct mutations to watch.
      if (scope.targetFinding.canTarget(target)) {
        this.observer.observe(target, OBSERVER_INIT);
      }
    },
    enableOnSubtree: function(target) {
      this.watchSubtree(target);
      if (target === document && document.readyState !== 'complete') {
        this.installOnLoad();
      } else {
        this.installNewSubtree(target);
      }
    },
    installNewSubtree: function(target) {
      forEach(this.findElements(target), this.addElement, this);
    },
    findElements: function(target) {
      if (target.querySelectorAll) {
        return target.querySelectorAll(SELECTOR);
      }
      return [];
    },
    removeElement: function(el) {
      this.removeCallback(el);
    },
    addElement: function(el) {
      this.addCallback(el);
    },
    elementChanged: function(el, oldValue) {
      this.changedCallback(el, oldValue);
    },
    concatLists: function(accum, list) {
      return accum.concat(toArray(list));
    },
    // register all touch-action = none nodes on document load
    installOnLoad: function() {
      document.addEventListener('readystatechange', function() {
        if (document.readyState === 'complete') {
          this.installNewSubtree(document);
        }
      }.bind(this));
    },
    isElement: function(n) {
      return n.nodeType === Node.ELEMENT_NODE;
    },
    flattenMutationTree: function(inNodes) {
      // find children with touch-action
      var tree = map(inNodes, this.findElements, this);
      // make sure the added nodes are accounted for
      tree.push(filter(inNodes, this.isElement));
      // flatten the list
      return tree.reduce(this.concatLists, []);
    },
    mutationWatcher: function(mutations) {
      mutations.forEach(this.mutationHandler, this);
    },
    mutationHandler: function(m) {
      if (m.type === 'childList') {
        var added = this.flattenMutationTree(m.addedNodes);
        added.forEach(this.addElement, this);
        var removed = this.flattenMutationTree(m.removedNodes);
        removed.forEach(this.removeElement, this);
      } else if (m.type === 'attributes') {
        this.elementChanged(m.target, m.oldValue);
      }
    }
  };

  if (!MO) {
    Installer.prototype.watchSubtree = function(){
      console.warn('PointerEventsPolyfill: MutationObservers not found, touch-action will not be dynamically detected');
    };
  }

  scope.Installer = Installer;
})(window.PointerEventsPolyfill);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function (scope) {
  var dispatcher = scope.dispatcher;
  var pointermap = dispatcher.pointermap;
  // radius around touchend that swallows mouse events
  var DEDUP_DIST = 25;

  var WHICH_TO_BUTTONS = [0, 1, 4, 2];

  var HAS_BUTTONS = false;
  try {
    HAS_BUTTONS = new MouseEvent('test', {buttons: 1}).buttons === 1;
  } catch (e) {}

  // handler block for native mouse events
  var mouseEvents = {
    POINTER_ID: 1,
    POINTER_TYPE: 'mouse',
    events: [
      'mousedown',
      'mousemove',
      'mouseup',
      'mouseover',
      'mouseout'
    ],
    register: function(target) {
      dispatcher.listen(target, this.events);
    },
    unregister: function(target) {
      dispatcher.unlisten(target, this.events);
    },
    lastTouches: [],
    // collide with the global mouse listener
    isEventSimulatedFromTouch: function(inEvent) {
      var lts = this.lastTouches;
      var x = inEvent.clientX, y = inEvent.clientY;
      for (var i = 0, l = lts.length, t; i < l && (t = lts[i]); i++) {
        // simulated mouse events will be swallowed near a primary touchend
        var dx = Math.abs(x - t.x), dy = Math.abs(y - t.y);
        if (dx <= DEDUP_DIST && dy <= DEDUP_DIST) {
          return true;
        }
      }
    },
    prepareEvent: function(inEvent) {
      var e = dispatcher.cloneEvent(inEvent);
      // forward mouse preventDefault
      var pd = e.preventDefault;
      e.preventDefault = function() {
        inEvent.preventDefault();
        pd();
      };
      e.pointerId = this.POINTER_ID;
      e.isPrimary = true;
      e.pointerType = this.POINTER_TYPE;
      if (!HAS_BUTTONS) {
        e.buttons = WHICH_TO_BUTTONS[e.which] || 0;
      }
      return e;
    },
    mousedown: function(inEvent) {
      if (!this.isEventSimulatedFromTouch(inEvent)) {
        var p = pointermap.has(this.POINTER_ID);
        // TODO(dfreedman) workaround for some elements not sending mouseup
        // http://crbug/149091
        if (p) {
          this.cancel(inEvent);
        }
        var e = this.prepareEvent(inEvent);
        pointermap.set(this.POINTER_ID, inEvent);
        dispatcher.down(e);
      }
    },
    mousemove: function(inEvent) {
      if (!this.isEventSimulatedFromTouch(inEvent)) {
        var e = this.prepareEvent(inEvent);
        dispatcher.move(e);
      }
    },
    mouseup: function(inEvent) {
      if (!this.isEventSimulatedFromTouch(inEvent)) {
        var p = pointermap.get(this.POINTER_ID);
        if (p && p.button === inEvent.button) {
          var e = this.prepareEvent(inEvent);
          dispatcher.up(e);
          this.cleanupMouse();
        }
      }
    },
    mouseover: function(inEvent) {
      if (!this.isEventSimulatedFromTouch(inEvent)) {
        var e = this.prepareEvent(inEvent);
        dispatcher.enterOver(e);
      }
    },
    mouseout: function(inEvent) {
      if (!this.isEventSimulatedFromTouch(inEvent)) {
        var e = this.prepareEvent(inEvent);
        dispatcher.leaveOut(e);
      }
    },
    cancel: function(inEvent) {
      var e = this.prepareEvent(inEvent);
      dispatcher.cancel(e);
      this.cleanupMouse();
    },
    cleanupMouse: function() {
      pointermap['delete'](this.POINTER_ID);
    }
  };

  scope.mouseEvents = mouseEvents;
})(window.PointerEventsPolyfill);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {
  var dispatcher = scope.dispatcher;
  var captureInfo = dispatcher.captureInfo;
  var findTarget = scope.findTarget;
  var allShadows = scope.targetFinding.allShadows.bind(scope.targetFinding);
  var pointermap = dispatcher.pointermap;
  var touchMap = Array.prototype.map.call.bind(Array.prototype.map);
  // This should be long enough to ignore compat mouse events made by touch
  var DEDUP_TIMEOUT = 2500;
  var CLICK_COUNT_TIMEOUT = 200;
  var ATTRIB = 'touch-action';
  var INSTALLER;
  // The presence of touch event handlers blocks scrolling, and so we must be careful to
  // avoid adding handlers unnecessarily.  Chrome plans to add a touch-action-delay property
  // (crbug.com/329559) to address this, and once we have that we can opt-in to a simpler
  // handler registration mechanism.  Rather than try to predict how exactly to opt-in to
  // that we'll just leave this disabled until there is a build of Chrome to test.
  var HAS_TOUCH_ACTION_DELAY = false;
  
  // handler block for native touch events
  var touchEvents = {
    events: [
      'touchstart',
      'touchmove',
      'touchend',
      'touchcancel'
    ],
    register: function(target) {
      if (HAS_TOUCH_ACTION_DELAY) {
        dispatcher.listen(target, this.events);
      } else {
        INSTALLER.enableOnSubtree(target);
      }
    },
    unregister: function(target) {
      if (HAS_TOUCH_ACTION_DELAY) {
        dispatcher.unlisten(target, this.events);
      } else {
        // TODO(dfreedman): is it worth it to disconnect the MO?
      }
    },
    elementAdded: function(el) {
      var a = el.getAttribute(ATTRIB);
      var st = this.touchActionToScrollType(a);
      if (st) {
        el._scrollType = st;
        dispatcher.listen(el, this.events);
        // set touch-action on shadows as well
        allShadows(el).forEach(function(s) {
          s._scrollType = st;
          dispatcher.listen(s, this.events);
        }, this);
      }
    },
    elementRemoved: function(el) {
      el._scrollType = undefined;
      dispatcher.unlisten(el, this.events);
      // remove touch-action from shadow
      allShadows(el).forEach(function(s) {
        s._scrollType = undefined;
        dispatcher.unlisten(s, this.events);
      }, this);
    },
    elementChanged: function(el, oldValue) {
      var a = el.getAttribute(ATTRIB);
      var st = this.touchActionToScrollType(a);
      var oldSt = this.touchActionToScrollType(oldValue);
      // simply update scrollType if listeners are already established
      if (st && oldSt) {
        el._scrollType = st;
        allShadows(el).forEach(function(s) {
          s._scrollType = st;
        }, this);
      } else if (oldSt) {
        this.elementRemoved(el);
      } else if (st) {
        this.elementAdded(el);
      }
    },
    scrollTypes: {
      EMITTER: 'none',
      XSCROLLER: 'pan-x',
      YSCROLLER: 'pan-y',
      SCROLLER: /^(?:pan-x pan-y)|(?:pan-y pan-x)|auto$/
    },
    touchActionToScrollType: function(touchAction) {
      var t = touchAction;
      var st = this.scrollTypes;
      if (t === 'none') {
        return 'none';
      } else if (t === st.XSCROLLER) {
        return 'X';
      } else if (t === st.YSCROLLER) {
        return 'Y';
      } else if (st.SCROLLER.exec(t)) {
        return 'XY';
      }
    },
    POINTER_TYPE: 'touch',
    firstTouch: null,
    isPrimaryTouch: function(inTouch) {
      return this.firstTouch === inTouch.identifier;
    },
    setPrimaryTouch: function(inTouch) {
      // set primary touch if there no pointers, or the only pointer is the mouse
      if (pointermap.pointers() === 0 || (pointermap.pointers() === 1 && pointermap.has(1))) {
        this.firstTouch = inTouch.identifier;
        this.firstXY = {X: inTouch.clientX, Y: inTouch.clientY};
        this.scrolling = false;
        this.cancelResetClickCount();
      }
    },
    removePrimaryPointer: function(inPointer) {
      if (inPointer.isPrimary) {
        this.firstTouch = null;
        this.firstXY = null;
        this.resetClickCount();
      }
    },
    clickCount: 0,
    resetId: null,
    resetClickCount: function() {
      var fn = function() {
        this.clickCount = 0;
        this.resetId = null;
      }.bind(this);
      this.resetId = setTimeout(fn, CLICK_COUNT_TIMEOUT);
    },
    cancelResetClickCount: function() {
      if (this.resetId) {
        clearTimeout(this.resetId);
      }
    },
    typeToButtons: function(type) {
      var ret = 0;
      if (type === 'touchstart' || type === 'touchmove') {
        ret = 1;
      }
      return ret;
    },
    touchToPointer: function(inTouch) {
      var cte = this.currentTouchEvent;
      var e = dispatcher.cloneEvent(inTouch);
      // Spec specifies that pointerId 1 is reserved for Mouse.
      // Touch identifiers can start at 0.
      // Add 2 to the touch identifier for compatibility.
      var id = e.pointerId = inTouch.identifier + 2;
      e.target = captureInfo[id] || findTarget(e);
      e.bubbles = true;
      e.cancelable = true;
      e.detail = this.clickCount;
      e.button = 0;
      e.buttons = this.typeToButtons(cte.type);
      e.width = inTouch.webkitRadiusX || inTouch.radiusX || 0;
      e.height = inTouch.webkitRadiusY || inTouch.radiusY || 0;
      e.pressure = inTouch.webkitForce || inTouch.force || 0.5;
      e.isPrimary = this.isPrimaryTouch(inTouch);
      e.pointerType = this.POINTER_TYPE;
      // forward touch preventDefaults
      var self = this;
      e.preventDefault = function() {
        self.scrolling = false;
        self.firstXY = null;
        cte.preventDefault();
      };
      return e;
    },
    processTouches: function(inEvent, inFunction) {
      var tl = inEvent.changedTouches;
      this.currentTouchEvent = inEvent;
      for (var i = 0, t; i < tl.length; i++) {
        t = tl[i];
        inFunction.call(this, this.touchToPointer(t));
      }
    },
    // For single axis scrollers, determines whether the element should emit
    // pointer events or behave as a scroller
    shouldScroll: function(inEvent) {
      if (this.firstXY) {
        var ret;
        var scrollAxis = inEvent.currentTarget._scrollType;
        if (scrollAxis === 'none') {
          // this element is a touch-action: none, should never scroll
          ret = false;
        } else if (scrollAxis === 'XY') {
          // this element should always scroll
          ret = true;
        } else {
          var t = inEvent.changedTouches[0];
          // check the intended scroll axis, and other axis
          var a = scrollAxis;
          var oa = scrollAxis === 'Y' ? 'X' : 'Y';
          var da = Math.abs(t['client' + a] - this.firstXY[a]);
          var doa = Math.abs(t['client' + oa] - this.firstXY[oa]);
          // if delta in the scroll axis > delta other axis, scroll instead of
          // making events
          ret = da >= doa;
        }
        this.firstXY = null;
        return ret;
      }
    },
    findTouch: function(inTL, inId) {
      for (var i = 0, l = inTL.length, t; i < l && (t = inTL[i]); i++) {
        if (t.identifier === inId) {
          return true;
        }
      }
    },
    // In some instances, a touchstart can happen without a touchend. This
    // leaves the pointermap in a broken state.
    // Therefore, on every touchstart, we remove the touches that did not fire a
    // touchend event.
    // To keep state globally consistent, we fire a
    // pointercancel for this "abandoned" touch
    vacuumTouches: function(inEvent) {
      var tl = inEvent.touches;
      // pointermap.pointers() should be < tl.length here, as the touchstart has not
      // been processed yet.
      if (pointermap.pointers() >= tl.length) {
        var d = [];
        pointermap.forEach(function(value, key) {
          // Never remove pointerId == 1, which is mouse.
          // Touch identifiers are 2 smaller than their pointerId, which is the
          // index in pointermap.
          if (key !== 1 && !this.findTouch(tl, key - 2)) {
            var p = value.out;
            d.push(p);
          }
        }, this);
        d.forEach(this.cancelOut, this);
      }
    },
    touchstart: function(inEvent) {
      this.vacuumTouches(inEvent);
      this.setPrimaryTouch(inEvent.changedTouches[0]);
      this.dedupSynthMouse(inEvent);
      if (!this.scrolling) {
        this.clickCount++;
        this.processTouches(inEvent, this.overDown);
      }
    },
    overDown: function(inPointer) {
      var p = pointermap.set(inPointer.pointerId, {
        target: inPointer.target,
        out: inPointer,
        outTarget: inPointer.target
      });
      dispatcher.over(inPointer);
      dispatcher.enter(inPointer);
      dispatcher.down(inPointer);
    },
    touchmove: function(inEvent) {
      if (!this.scrolling) {
        if (this.shouldScroll(inEvent)) {
          this.scrolling = true;
          this.touchcancel(inEvent);
        } else {
          inEvent.preventDefault();
          this.processTouches(inEvent, this.moveOverOut);
        }
      }
    },
    moveOverOut: function(inPointer) {
      var event = inPointer;
      var pointer = pointermap.get(event.pointerId);
      // a finger drifted off the screen, ignore it
      if (!pointer) {
        return;
      }
      var outEvent = pointer.out;
      var outTarget = pointer.outTarget;
      dispatcher.move(event);
      if (outEvent && outTarget !== event.target) {
        outEvent.relatedTarget = event.target;
        event.relatedTarget = outTarget;
        // recover from retargeting by shadow
        outEvent.target = outTarget;
        if (event.target) {
          dispatcher.leaveOut(outEvent);
          dispatcher.enterOver(event);
        } else {
          // clean up case when finger leaves the screen
          event.target = outTarget;
          event.relatedTarget = null;
          this.cancelOut(event);
        }
      }
      pointer.out = event;
      pointer.outTarget = event.target;
    },
    touchend: function(inEvent) {
      this.dedupSynthMouse(inEvent);
      this.processTouches(inEvent, this.upOut);
    },
    upOut: function(inPointer) {
      if (!this.scrolling) {
        dispatcher.up(inPointer);
        dispatcher.out(inPointer);
        dispatcher.leave(inPointer);
      }
      this.cleanUpPointer(inPointer);
    },
    touchcancel: function(inEvent) {
      this.processTouches(inEvent, this.cancelOut);
    },
    cancelOut: function(inPointer) {
      dispatcher.cancel(inPointer);
      dispatcher.out(inPointer);
      dispatcher.leave(inPointer);
      this.cleanUpPointer(inPointer);
    },
    cleanUpPointer: function(inPointer) {
      pointermap['delete'](inPointer.pointerId);
      this.removePrimaryPointer(inPointer);
    },
    // prevent synth mouse events from creating pointer events
    dedupSynthMouse: function(inEvent) {
      var lts = scope.mouseEvents.lastTouches;
      var t = inEvent.changedTouches[0];
      // only the primary finger will synth mouse events
      if (this.isPrimaryTouch(t)) {
        // remember x/y of last touch
        var lt = {x: t.clientX, y: t.clientY};
        lts.push(lt);
        var fn = (function(lts, lt){
          var i = lts.indexOf(lt);
          if (i > -1) {
            lts.splice(i, 1);
          }
        }).bind(null, lts, lt);
        setTimeout(fn, DEDUP_TIMEOUT);
      }
    }
  };

  if (!HAS_TOUCH_ACTION_DELAY) {
    INSTALLER = new scope.Installer(touchEvents.elementAdded, touchEvents.elementRemoved, touchEvents.elementChanged, touchEvents);
  }

  scope.touchEvents = touchEvents;
})(window.PointerEventsPolyfill);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {
  var dispatcher = scope.dispatcher;
  var pointermap = dispatcher.pointermap;
  var HAS_BITMAP_TYPE = window.MSPointerEvent && typeof window.MSPointerEvent.MSPOINTER_TYPE_MOUSE === 'number';
  var msEvents = {
    events: [
      'MSPointerDown',
      'MSPointerMove',
      'MSPointerUp',
      'MSPointerOut',
      'MSPointerOver',
      'MSPointerCancel',
      'MSGotPointerCapture',
      'MSLostPointerCapture'
    ],
    register: function(target) {
      dispatcher.listen(target, this.events);
    },
    unregister: function(target) {
      dispatcher.unlisten(target, this.events);
    },
    POINTER_TYPES: [
      '',
      'unavailable',
      'touch',
      'pen',
      'mouse'
    ],
    prepareEvent: function(inEvent) {
      var e = inEvent;
      if (HAS_BITMAP_TYPE) {
        e = dispatcher.cloneEvent(inEvent);
        e.pointerType = this.POINTER_TYPES[inEvent.pointerType];
      }
      return e;
    },
    cleanup: function(id) {
      pointermap['delete'](id);
    },
    MSPointerDown: function(inEvent) {
      pointermap.set(inEvent.pointerId, inEvent);
      var e = this.prepareEvent(inEvent);
      dispatcher.down(e);
    },
    MSPointerMove: function(inEvent) {
      var e = this.prepareEvent(inEvent);
      dispatcher.move(e);
    },
    MSPointerUp: function(inEvent) {
      var e = this.prepareEvent(inEvent);
      dispatcher.up(e);
      this.cleanup(inEvent.pointerId);
    },
    MSPointerOut: function(inEvent) {
      var e = this.prepareEvent(inEvent);
      dispatcher.leaveOut(e);
    },
    MSPointerOver: function(inEvent) {
      var e = this.prepareEvent(inEvent);
      dispatcher.enterOver(e);
    },
    MSPointerCancel: function(inEvent) {
      var e = this.prepareEvent(inEvent);
      dispatcher.cancel(e);
      this.cleanup(inEvent.pointerId);
    },
    MSLostPointerCapture: function(inEvent) {
      var e = dispatcher.makeEvent('lostpointercapture', inEvent);
      dispatcher.dispatchEvent(e);
    },
    MSGotPointerCapture: function(inEvent) {
      var e = dispatcher.makeEvent('gotpointercapture', inEvent);
      dispatcher.dispatchEvent(e);
    }
  };

  scope.msEvents = msEvents;
})(window.PointerEventsPolyfill);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

/**
 * This module contains the handlers for native platform events.
 * From here, the dispatcher is called to create unified pointer events.
 * Included are touch events (v1), mouse events, and MSPointerEvents.
 */
(function(scope) {
  var dispatcher = scope.dispatcher;

  // only activate if this platform does not have pointer events
  if (window.PointerEvent !== scope.PointerEvent) {

    if (window.navigator.msPointerEnabled) {
      var tp = window.navigator.msMaxTouchPoints;
      Object.defineProperty(window.navigator, 'maxTouchPoints', {
        value: tp,
        enumerable: true
      });
      dispatcher.registerSource('ms', scope.msEvents);
    } else {
      dispatcher.registerSource('mouse', scope.mouseEvents);
      if (window.ontouchstart !== undefined) {
        dispatcher.registerSource('touch', scope.touchEvents);
      }
    }

    dispatcher.register(document);
  }
})(window.PointerEventsPolyfill);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {
  var dispatcher = scope.dispatcher;
  var n = window.navigator;
  var s, r;
  function assertDown(id) {
    if (!dispatcher.pointermap.has(id)) {
      throw new Error('InvalidPointerId');
    }
  }
  if (n.msPointerEnabled) {
    s = function(pointerId) {
      assertDown(pointerId);
      this.msSetPointerCapture(pointerId);
    };
    r = function(pointerId) {
      assertDown(pointerId);
      this.msReleasePointerCapture(pointerId);
    };
  } else {
    s = function setPointerCapture(pointerId) {
      assertDown(pointerId);
      dispatcher.setCapture(pointerId, this);
    };
    r = function releasePointerCapture(pointerId) {
      assertDown(pointerId);
      dispatcher.releaseCapture(pointerId, this);
    };
  }
  if (window.Element && !Element.prototype.setPointerCapture) {
    Object.defineProperties(Element.prototype, {
      'setPointerCapture': {
        value: s
      },
      'releasePointerCapture': {
        value: r
      }
    });
  }
})(window.PointerEventsPolyfill);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

/**
 * PointerGestureEvent is the constructor for all PointerGesture events.
 *
 * @module PointerGestures
 * @class PointerGestureEvent
 * @extends UIEvent
 * @constructor
 * @param {String} inType Event type
 * @param {Object} [inDict] Dictionary of properties to initialize on the event
 */

function PointerGestureEvent(inType, inDict) {
  var dict = inDict || {};
  var e = document.createEvent('Event');
  var props = {
    bubbles: Boolean(dict.bubbles) === dict.bubbles || true,
    cancelable: Boolean(dict.cancelable) === dict.cancelable || true
  };

  e.initEvent(inType, props.bubbles, props.cancelable);

  var keys = Object.keys(dict), k;
  for (var i = 0; i < keys.length; i++) {
    k = keys[i];
    e[k] = dict[k];
  }

  e.preventTap = this.preventTap;

  return e;
}

/**
 * Allows for any gesture to prevent the tap gesture.
 *
 * @method preventTap
 */
PointerGestureEvent.prototype.preventTap = function() {
  this.tapPrevented = true;
};


/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {
  /**
   * This class contains the gesture recognizers that create the PointerGesture
   * events.
   *
   * @class PointerGestures
   * @static
   */
  scope = scope || {};
  scope.utils = {
    LCA: {
      // Determines the lowest node in the ancestor chain of a and b
      find: function(a, b) {
        if (a === b) {
          return a;
        }
        // fast case, a is a direct descendant of b or vice versa
        if (a.contains) {
          if (a.contains(b)) {
            return a;
          }
          if (b.contains(a)) {
            return b;
          }
        }
        var adepth = this.depth(a);
        var bdepth = this.depth(b);
        var d = adepth - bdepth;
        if (d > 0) {
          a = this.walk(a, d);
        } else {
          b = this.walk(b, -d);
        }
        while(a && b && a !== b) {
          a = this.walk(a, 1);
          b = this.walk(b, 1);
        }
        return a;
      },
      walk: function(n, u) {
        for (var i = 0; i < u; i++) {
          n = n.parentNode;
        }
        return n;
      },
      depth: function(n) {
        var d = 0;
        while(n) {
          d++;
          n = n.parentNode;
        }
        return d;
      }
    }
  };
  scope.findLCA = function(a, b) {
    return scope.utils.LCA.find(a, b);
  }
  window.PointerGestures = scope;
})(window.PointerGestures);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

/**
 * This module implements an map of pointer states
 */
(function(scope) {
  var USE_MAP = window.Map && window.Map.prototype.forEach;
  var POINTERS_FN = function(){ return this.size; };
  function PointerMap() {
    if (USE_MAP) {
      var m = new Map();
      m.pointers = POINTERS_FN;
      return m;
    } else {
      this.keys = [];
      this.values = [];
    }
  }

  PointerMap.prototype = {
    set: function(inId, inEvent) {
      var i = this.keys.indexOf(inId);
      if (i > -1) {
        this.values[i] = inEvent;
      } else {
        this.keys.push(inId);
        this.values.push(inEvent);
      }
    },
    has: function(inId) {
      return this.keys.indexOf(inId) > -1;
    },
    'delete': function(inId) {
      var i = this.keys.indexOf(inId);
      if (i > -1) {
        this.keys.splice(i, 1);
        this.values.splice(i, 1);
      }
    },
    get: function(inId) {
      var i = this.keys.indexOf(inId);
      return this.values[i];
    },
    clear: function() {
      this.keys.length = 0;
      this.values.length = 0;
    },
    // return value, key, map
    forEach: function(callback, thisArg) {
      this.values.forEach(function(v, i) {
        callback.call(thisArg, v, this.keys[i], this);
      }, this);
    },
    pointers: function() {
      return this.keys.length;
    }
  };

  scope.PointerMap = PointerMap;
})(window.PointerGestures);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

(function(scope) {
  var CLONE_PROPS = [
    // MouseEvent
    'bubbles',
    'cancelable',
    'view',
    'detail',
    'screenX',
    'screenY',
    'clientX',
    'clientY',
    'ctrlKey',
    'altKey',
    'shiftKey',
    'metaKey',
    'button',
    'relatedTarget',
    // DOM Level 3
    'buttons',
    // PointerEvent
    'pointerId',
    'width',
    'height',
    'pressure',
    'tiltX',
    'tiltY',
    'pointerType',
    'hwTimestamp',
    'isPrimary',
    // event instance
    'type',
    'target',
    'currentTarget',
    'screenX',
    'screenY',
    'pageX',
    'pageY',
    'tapPrevented'
  ];

  var CLONE_DEFAULTS = [
    // MouseEvent
    false,
    false,
    null,
    null,
    0,
    0,
    0,
    0,
    false,
    false,
    false,
    false,
    0,
    null,
    // DOM Level 3
    0,
    // PointerEvent
    0,
    0,
    0,
    0,
    0,
    0,
    '',
    0,
    false,
    // event instance
    '',
    null,
    null,
    0,
    0,
    0,
    0
  ];

  var dispatcher = {
    handledEvents: new WeakMap(),
    targets: new WeakMap(),
    handlers: {},
    recognizers: {},
    events: {},
    // Add a new gesture recognizer to the event listeners.
    // Recognizer needs an `events` property.
    registerRecognizer: function(inName, inRecognizer) {
      var r = inRecognizer;
      this.recognizers[inName] = r;
      r.events.forEach(function(e) {
        if (r[e]) {
          this.events[e] = true;
          var f = r[e].bind(r);
          this.addHandler(e, f);
        }
      }, this);
    },
    addHandler: function(inEvent, inFn) {
      var e = inEvent;
      if (!this.handlers[e]) {
        this.handlers[e] = [];
      }
      this.handlers[e].push(inFn);
    },
    // add event listeners for inTarget
    registerTarget: function(inTarget) {
      this.listen(Object.keys(this.events), inTarget);
    },
    // remove event listeners for inTarget
    unregisterTarget: function(inTarget) {
      this.unlisten(Object.keys(this.events), inTarget);
    },
    // LISTENER LOGIC
    eventHandler: function(inEvent) {
      if (this.handledEvents.get(inEvent)) {
        return;
      }
      var type = inEvent.type, fns = this.handlers[type];
      if (fns) {
        this.makeQueue(fns, inEvent);
      }
      this.handledEvents.set(inEvent, true);
    },
    // queue event for async dispatch
    makeQueue: function(inHandlerFns, inEvent) {
      // must clone events to keep the (possibly shadowed) target correct for
      // async dispatching
      var e = this.cloneEvent(inEvent);
      requestAnimationFrame(this.runQueue.bind(this, inHandlerFns, e));
    },
    // Dispatch the queued events
    runQueue: function(inHandlers, inEvent) {
      this.currentPointerId = inEvent.pointerId;
      for (var i = 0, f, l = inHandlers.length; (i < l) && (f = inHandlers[i]); i++) {
        f(inEvent);
      }
      this.currentPointerId = 0;
    },
    // set up event listeners
    listen: function(inEvents, inTarget) {
      inEvents.forEach(function(e) {
        this.addEvent(e, this.boundHandler, false, inTarget);
      }, this);
    },
    // remove event listeners
    unlisten: function(inEvents) {
      inEvents.forEach(function(e) {
        this.removeEvent(e, this.boundHandler, false, inTarget);
      }, this);
    },
    addEvent: function(inEventName, inEventHandler, inCapture, inTarget) {
      inTarget.addEventListener(inEventName, inEventHandler, inCapture);
    },
    removeEvent: function(inEventName, inEventHandler, inCapture, inTarget) {
      inTarget.removeEventListener(inEventName, inEventHandler, inCapture);
    },
    // EVENT CREATION AND TRACKING
    // Creates a new Event of type `inType`, based on the information in
    // `inEvent`.
    makeEvent: function(inType, inDict) {
      return new PointerGestureEvent(inType, inDict);
    },
    /*
     * Returns a snapshot of inEvent, with writable properties.
     *
     * @method cloneEvent
     * @param {Event} inEvent An event that contains properties to copy.
     * @return {Object} An object containing shallow copies of `inEvent`'s
     *    properties.
     */
    cloneEvent: function(inEvent) {
      var eventCopy = {}, p;
      for (var i = 0; i < CLONE_PROPS.length; i++) {
        p = CLONE_PROPS[i];
        eventCopy[p] = inEvent[p] || CLONE_DEFAULTS[i];
      }
      return eventCopy;
    },
    // Dispatches the event to its target.
    dispatchEvent: function(inEvent, inTarget) {
      var t = inTarget || this.targets.get(inEvent);
      if (t) {
        t.dispatchEvent(inEvent);
        if (inEvent.tapPrevented) {
          this.preventTap(this.currentPointerId);
        }
      }
    },
    asyncDispatchEvent: function(inEvent, inTarget) {
      requestAnimationFrame(this.dispatchEvent.bind(this, inEvent, inTarget));
    },
    preventTap: function(inPointerId) {
      var t = this.recognizers.tap;
      if (t){
        t.preventTap(inPointerId);
      }
    }
  };
  dispatcher.boundHandler = dispatcher.eventHandler.bind(dispatcher);
  // recognizers call into the dispatcher and load later
  // solve the chicken and egg problem by having registerScopes module run last
  dispatcher.registerQueue = [];
  dispatcher.immediateRegister = false;
  scope.dispatcher = dispatcher;
  /**
   * Enable gesture events for a given scope, typically
   * [ShadowRoots](https://dvcs.w3.org/hg/webcomponents/raw-file/tip/spec/shadow/index.html#shadow-root-object).
   *
   * @for PointerGestures
   * @method register
   * @param {ShadowRoot} scope A top level scope to enable gesture
   * support on.
   */
  scope.register = function(inScope) {
    if (dispatcher.immediateRegister) {
      var pe = window.PointerEventsPolyfill;
      if (pe) {
        pe.register(inScope);
      }
      scope.dispatcher.registerTarget(inScope);
    } else {
      dispatcher.registerQueue.push(inScope);
    }
  };
  scope.register(document);
})(window.PointerGestures);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

/**
 * This event is fired when a pointer is held down for 200ms.
 *
 * @module PointerGestures
 * @submodule Events
 * @class hold
 */
/**
 * Type of pointer that made the holding event.
 * @type String
 * @property pointerType
 */
/**
 * Screen X axis position of the held pointer
 * @type Number
 * @property clientX
 */
/**
 * Screen Y axis position of the held pointer
 * @type Number
 * @property clientY
 */
/**
 * Type of pointer that made the holding event.
 * @type String
 * @property pointerType
 */
/**
 * This event is fired every 200ms while a pointer is held down.
 *
 * @class holdpulse
 * @extends hold
 */
/**
 * Milliseconds pointer has been held down.
 * @type Number
 * @property holdTime
 */
/**
 * This event is fired when a held pointer is released or moved.
 *
 * @class released
 */

(function(scope) {
  var dispatcher = scope.dispatcher;
  var hold = {
    // wait at least HOLD_DELAY ms between hold and pulse events
    HOLD_DELAY: 200,
    // pointer can move WIGGLE_THRESHOLD pixels before not counting as a hold
    WIGGLE_THRESHOLD: 16,
    events: [
      'pointerdown',
      'pointermove',
      'pointerup',
      'pointercancel'
    ],
    heldPointer: null,
    holdJob: null,
    pulse: function() {
      var hold = Date.now() - this.heldPointer.timeStamp;
      var type = this.held ? 'holdpulse' : 'hold';
      this.fireHold(type, hold);
      this.held = true;
    },
    cancel: function() {
      clearInterval(this.holdJob);
      if (this.held) {
        this.fireHold('release');
      }
      this.held = false;
      this.heldPointer = null;
      this.target = null;
      this.holdJob = null;
    },
    pointerdown: function(inEvent) {
      if (inEvent.isPrimary && !this.heldPointer) {
        this.heldPointer = inEvent;
        this.target = inEvent.target;
        this.holdJob = setInterval(this.pulse.bind(this), this.HOLD_DELAY);
      }
    },
    pointerup: function(inEvent) {
      if (this.heldPointer && this.heldPointer.pointerId === inEvent.pointerId) {
        this.cancel();
      }
    },
    pointercancel: function(inEvent) {
      this.cancel();
    },
    pointermove: function(inEvent) {
      if (this.heldPointer && this.heldPointer.pointerId === inEvent.pointerId) {
        var x = inEvent.clientX - this.heldPointer.clientX;
        var y = inEvent.clientY - this.heldPointer.clientY;
        if ((x * x + y * y) > this.WIGGLE_THRESHOLD) {
          this.cancel();
        }
      }
    },
    fireHold: function(inType, inHoldTime) {
      var p = {
        pointerType: this.heldPointer.pointerType,
        clientX: this.heldPointer.clientX,
        clientY: this.heldPointer.clientY
      };
      if (inHoldTime) {
        p.holdTime = inHoldTime;
      }
      var e = dispatcher.makeEvent(inType, p);
      dispatcher.dispatchEvent(e, this.target);
      if (e.tapPrevented) {
        dispatcher.preventTap(this.heldPointer.pointerId);
      }
    }
  };
  dispatcher.registerRecognizer('hold', hold);
})(window.PointerGestures);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

/**
 * This event denotes the beginning of a series of tracking events.
 *
 * @module PointerGestures
 * @submodule Events
 * @class trackstart
 */
/**
 * Pixels moved in the x direction since trackstart.
 * @type Number
 * @property dx
 */
/**
 * Pixes moved in the y direction since trackstart.
 * @type Number
 * @property dy
 */
/**
 * Pixels moved in the x direction since the last track.
 * @type Number
 * @property ddx
 */
/**
 * Pixles moved in the y direction since the last track.
 * @type Number
 * @property ddy
 */
/**
 * The clientX position of the track gesture.
 * @type Number
 * @property clientX
 */
/**
 * The clientY position of the track gesture.
 * @type Number
 * @property clientY
 */
/**
 * The pageX position of the track gesture.
 * @type Number
 * @property pageX
 */
/**
 * The pageY position of the track gesture.
 * @type Number
 * @property pageY
 */
/**
 * The screenX position of the track gesture.
 * @type Number
 * @property screenX
 */
/**
 * The screenY position of the track gesture.
 * @type Number
 * @property screenY
 */
/**
 * The last x axis direction of the pointer.
 * @type Number
 * @property xDirection
 */
/**
 * The last y axis direction of the pointer.
 * @type Number
 * @property yDirection
 */
/**
 * A shared object between all tracking events.
 * @type Object
 * @property trackInfo
 */
/**
 * The element currently under the pointer.
 * @type Element
 * @property relatedTarget
 */
/**
 * The type of pointer that make the track gesture.
 * @type String
 * @property pointerType
 */
/**
 *
 * This event fires for all pointer movement being tracked.
 *
 * @class track
 * @extends trackstart
 */
/**
 * This event fires when the pointer is no longer being tracked.
 *
 * @class trackend
 * @extends trackstart
 */

 (function(scope) {
   var dispatcher = scope.dispatcher;
   var pointermap = new scope.PointerMap();
   var track = {
     events: [
       'pointerdown',
       'pointermove',
       'pointerup',
       'pointercancel'
     ],
     WIGGLE_THRESHOLD: 4,
     clampDir: function(inDelta) {
       return inDelta > 0 ? 1 : -1;
     },
     calcPositionDelta: function(inA, inB) {
       var x = 0, y = 0;
       if (inA && inB) {
         x = inB.pageX - inA.pageX;
         y = inB.pageY - inA.pageY;
       }
       return {x: x, y: y};
     },
     fireTrack: function(inType, inEvent, inTrackingData) {
       var t = inTrackingData;
       var d = this.calcPositionDelta(t.downEvent, inEvent);
       var dd = this.calcPositionDelta(t.lastMoveEvent, inEvent);
       if (dd.x) {
         t.xDirection = this.clampDir(dd.x);
       }
       if (dd.y) {
         t.yDirection = this.clampDir(dd.y);
       }
       var trackData = {
         dx: d.x,
         dy: d.y,
         ddx: dd.x,
         ddy: dd.y,
         clientX: inEvent.clientX,
         clientY: inEvent.clientY,
         pageX: inEvent.pageX,
         pageY: inEvent.pageY,
         screenX: inEvent.screenX,
         screenY: inEvent.screenY,
         xDirection: t.xDirection,
         yDirection: t.yDirection,
         trackInfo: t.trackInfo,
         relatedTarget: inEvent.target,
         pointerType: inEvent.pointerType
       };
       var e = dispatcher.makeEvent(inType, trackData);
       t.lastMoveEvent = inEvent;
       dispatcher.dispatchEvent(e, t.downTarget);
     },
     pointerdown: function(inEvent) {
       if (inEvent.isPrimary && (inEvent.pointerType === 'mouse' ? inEvent.buttons === 1 : true)) {
         var p = {
           downEvent: inEvent,
           downTarget: inEvent.target,
           trackInfo: {},
           lastMoveEvent: null,
           xDirection: 0,
           yDirection: 0,
           tracking: false
         };
         pointermap.set(inEvent.pointerId, p);
       }
     },
     pointermove: function(inEvent) {
       var p = pointermap.get(inEvent.pointerId);
       if (p) {
         if (!p.tracking) {
           var d = this.calcPositionDelta(p.downEvent, inEvent);
           var move = d.x * d.x + d.y * d.y;
           // start tracking only if finger moves more than WIGGLE_THRESHOLD
           if (move > this.WIGGLE_THRESHOLD) {
             p.tracking = true;
             this.fireTrack('trackstart', p.downEvent, p);
             this.fireTrack('track', inEvent, p);
           }
         } else {
           this.fireTrack('track', inEvent, p);
         }
       }
     },
     pointerup: function(inEvent) {
       var p = pointermap.get(inEvent.pointerId);
       if (p) {
         if (p.tracking) {
           this.fireTrack('trackend', inEvent, p);
         }
         pointermap.delete(inEvent.pointerId);
       }
     },
     pointercancel: function(inEvent) {
       this.pointerup(inEvent);
     }
   };
   dispatcher.registerRecognizer('track', track);
 })(window.PointerGestures);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

/**
 * This event denotes a rapid down/move/up sequence from a pointer.
 *
 * The event is sent to the first element the pointer went down on.
 *
 * @module PointerGestures
 * @submodule Events
 * @class flick
 */
/**
 * Signed velocity of the flick in the x direction.
 * @property xVelocity
 * @type Number
 */
/**
 * Signed velocity of the flick in the y direction.
 * @type Number
 * @property yVelocity
 */
/**
 * Unsigned total velocity of the flick.
 * @type Number
 * @property velocity
 */
/**
 * Angle of the flick in degrees, with 0 along the
 * positive x axis.
 * @type Number
 * @property angle
 */
/**
 * Axis with the greatest absolute velocity. Denoted
 * with 'x' or 'y'.
 * @type String
 * @property majorAxis
 */
/**
 * Type of the pointer that made the flick.
 * @type String
 * @property pointerType
 */

(function(scope) {
  var dispatcher = scope.dispatcher;
  var flick = {
    // TODO(dfreedman): value should be low enough for low speed flicks, but
    // high enough to remove accidental flicks
    MIN_VELOCITY: 0.5 /* px/ms */,
    MAX_QUEUE: 4,
    moveQueue: [],
    target: null,
    pointerId: null,
    events: [
      'pointerdown',
      'pointermove',
      'pointerup',
      'pointercancel'
    ],
    pointerdown: function(inEvent) {
      if (inEvent.isPrimary && !this.pointerId) {
        this.pointerId = inEvent.pointerId;
        this.target = inEvent.target;
        this.addMove(inEvent);
      }
    },
    pointermove: function(inEvent) {
      if (inEvent.pointerId === this.pointerId) {
        this.addMove(inEvent);
      }
    },
    pointerup: function(inEvent) {
      if (inEvent.pointerId === this.pointerId) {
        this.fireFlick(inEvent);
      }
      this.cleanup();
    },
    pointercancel: function(inEvent) {
      this.cleanup();
    },
    cleanup: function() {
      this.moveQueue = [];
      this.target = null;
      this.pointerId = null;
    },
    addMove: function(inEvent) {
      if (this.moveQueue.length >= this.MAX_QUEUE) {
        this.moveQueue.shift();
      }
      this.moveQueue.push(inEvent);
    },
    fireFlick: function(inEvent) {
      var e = inEvent;
      var l = this.moveQueue.length;
      var dt, dx, dy, tx, ty, tv, x = 0, y = 0, v = 0;
      // flick based off the fastest segment of movement
      for (var i = 0, m; i < l && (m = this.moveQueue[i]); i++) {
        dt = e.timeStamp - m.timeStamp;
        dx = e.clientX - m.clientX, dy = e.clientY - m.clientY;
        tx = dx / dt, ty = dy / dt, tv = Math.sqrt(tx * tx + ty * ty);
        if (tv > v) {
          x = tx, y = ty, v = tv;
        }
      }
      var ma = Math.abs(x) > Math.abs(y) ? 'x' : 'y';
      var a = this.calcAngle(x, y);
      if (Math.abs(v) >= this.MIN_VELOCITY) {
        var ev = dispatcher.makeEvent('flick', {
          xVelocity: x,
          yVelocity: y,
          velocity: v,
          angle: a,
          majorAxis: ma,
          pointerType: inEvent.pointerType
        });
        dispatcher.dispatchEvent(ev, this.target);
      }
    },
    calcAngle: function(inX, inY) {
      return (Math.atan2(inY, inX) * 180 / Math.PI);
    }
  };
  dispatcher.registerRecognizer('flick', flick);
})(window.PointerGestures);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

/*
 * Basic strategy: find the farthest apart points, use as diameter of circle
 * react to size change and rotation of the chord
 */

/**
 * @module PointerGestures
 * @submodule Events
 * @class pinch
 */
/**
 * Scale of the pinch zoom gesture
 * @property scale
 * @type Number
 */
/**
 * Center X position of pointers causing pinch
 * @property centerX
 * @type Number
 */
/**
 * Center Y position of pointers causing pinch
 * @property centerY
 * @type Number
 */

/**
 * @module PointerGestures
 * @submodule Events
 * @class rotate
 */
/**
 * Angle (in degrees) of rotation. Measured from starting positions of pointers.
 * @property angle
 * @type Number
 */
/**
 * Center X position of pointers causing rotation
 * @property centerX
 * @type Number
 */
/**
 * Center Y position of pointers causing rotation
 * @property centerY
 * @type Number
 */
(function(scope) {
  var dispatcher = scope.dispatcher;
  var pointermap = new scope.PointerMap();
  var RAD_TO_DEG = 180 / Math.PI;
  var pinch = {
    events: [
      'pointerdown',
      'pointermove',
      'pointerup',
      'pointercancel'
    ],
    reference: {},
    pointerdown: function(ev) {
      pointermap.set(ev.pointerId, ev);
      if (pointermap.pointers() == 2) {
        var points = this.calcChord();
        var angle = this.calcAngle(points);
        this.reference = {
          angle: angle,
          diameter: points.diameter,
          target: scope.findLCA(points.a.target, points.b.target)
        };
      }
    },
    pointerup: function(ev) {
      pointermap.delete(ev.pointerId);
    },
    pointermove: function(ev) {
      if (pointermap.has(ev.pointerId)) {
        pointermap.set(ev.pointerId, ev);
        if (pointermap.pointers() > 1) {
          this.calcPinchRotate();
        }
      }
    },
    pointercancel: function(ev) {
      this.pointerup(ev);
    },
    dispatchPinch: function(diameter, points) {
      var zoom = diameter / this.reference.diameter;
      var ev = dispatcher.makeEvent('pinch', {
        scale: zoom,
        centerX: points.center.x,
        centerY: points.center.y
      });
      dispatcher.dispatchEvent(ev, this.reference.target);
    },
    dispatchRotate: function(angle, points) {
      var diff = Math.round((angle - this.reference.angle) % 360);
      var ev = dispatcher.makeEvent('rotate', {
        angle: diff,
        centerX: points.center.x,
        centerY: points.center.y
      });
      dispatcher.dispatchEvent(ev, this.reference.target);
    },
    calcPinchRotate: function() {
      var points = this.calcChord();
      var diameter = points.diameter;
      var angle = this.calcAngle(points);
      if (diameter != this.reference.diameter) {
        this.dispatchPinch(diameter, points);
      }
      if (angle != this.reference.angle) {
        this.dispatchRotate(angle, points);
      }
    },
    calcChord: function() {
      var pointers = [];
      pointermap.forEach(function(p) {
        pointers.push(p);
      });
      var dist = 0;
      // start with at least two pointers
      var points = {a: pointers[0], b: pointers[1]};
      var x, y, d;
      for (var i = 0; i < pointers.length; i++) {
        var a = pointers[i];
        for (var j = i + 1; j < pointers.length; j++) {
          var b = pointers[j];
          x = Math.abs(a.clientX - b.clientX);
          y = Math.abs(a.clientY - b.clientY);
          d = x + y;
          if (d > dist) {
            dist = d;
            points = {a: a, b: b};
          }
        }
      }
      x = Math.abs(points.a.clientX + points.b.clientX) / 2;
      y = Math.abs(points.a.clientY + points.b.clientY) / 2;
      points.center = { x: x, y: y };
      points.diameter = dist;
      return points;
    },
    calcAngle: function(points) {
      var x = points.a.clientX - points.b.clientX;
      var y = points.a.clientY - points.b.clientY;
      return (360 + Math.atan2(y, x) * RAD_TO_DEG) % 360;
    },
  };
  dispatcher.registerRecognizer('pinch', pinch);
})(window.PointerGestures);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

/**
 * This event is fired when a pointer quickly goes down and up, and is used to
 * denote activation.
 *
 * Any gesture event can prevent the tap event from being created by calling
 * `event.preventTap`.
 *
 * Any pointer event can prevent the tap by setting the `tapPrevented` property
 * on itself.
 *
 * @module PointerGestures
 * @submodule Events
 * @class tap
 */
/**
 * X axis position of the tap.
 * @property x
 * @type Number
 */
/**
 * Y axis position of the tap.
 * @property y
 * @type Number
 */
/**
 * Type of the pointer that made the tap.
 * @property pointerType
 * @type String
 */
(function(scope) {
  var dispatcher = scope.dispatcher;
  var pointermap = new scope.PointerMap();
  var tap = {
    events: [
      'pointerdown',
      'pointermove',
      'pointerup',
      'pointercancel',
      'keyup'
    ],
    pointerdown: function(inEvent) {
      if (inEvent.isPrimary && !inEvent.tapPrevented) {
        pointermap.set(inEvent.pointerId, {
          target: inEvent.target,
          buttons: inEvent.buttons,
          x: inEvent.clientX,
          y: inEvent.clientY
        });
      }
    },
    pointermove: function(inEvent) {
      if (inEvent.isPrimary) {
        var start = pointermap.get(inEvent.pointerId);
        if (start) {
          if (inEvent.tapPrevented) {
            pointermap.delete(inEvent.pointerId);
          }
        }
      }
    },
    shouldTap: function(e, downState) {
      if (!e.tapPrevented) {
        if (e.pointerType === 'mouse') {
          // only allow left click to tap for mouse
          return downState.buttons === 1;
        } else {
          return true;
        }
      }
    },
    pointerup: function(inEvent) {
      var start = pointermap.get(inEvent.pointerId);
      if (start && this.shouldTap(inEvent, start)) {
        var t = scope.findLCA(start.target, inEvent.target);
        if (t) {
          var e = dispatcher.makeEvent('tap', {
            x: inEvent.clientX,
            y: inEvent.clientY,
            detail: inEvent.detail,
            pointerType: inEvent.pointerType
          });
          dispatcher.dispatchEvent(e, t);
        }
      }
      pointermap.delete(inEvent.pointerId);
    },
    pointercancel: function(inEvent) {
      pointermap.delete(inEvent.pointerId);
    },
    keyup: function(inEvent) {
      var code = inEvent.keyCode;
      // 32 == spacebar
      if (code === 32) {
        var t = inEvent.target;
        if (!(t instanceof HTMLInputElement || t instanceof HTMLTextAreaElement)) {
          dispatcher.dispatchEvent(dispatcher.makeEvent('tap', {
            x: 0,
            y: 0,
            detail: 0,
            pointerType: 'unavailable'
          }), t);
        }
      }
    },
    preventTap: function(inPointerId) {
      pointermap.delete(inPointerId);
    }
  };
  dispatcher.registerRecognizer('tap', tap);
})(window.PointerGestures);

/*
 * Copyright 2014 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */

/**
 * Because recognizers are loaded after dispatcher, we have to wait to register
 * scopes until after all the recognizers.
 */
(function(scope) {
  var dispatcher = scope.dispatcher;
  function registerScopes() {
    dispatcher.immediateRegister = true;
    var rq = dispatcher.registerQueue;
    rq.forEach(scope.register);
    rq.length = 0;
  }
  if (document.readyState === 'complete') {
    registerScopes();
  } else {
    // register scopes after a steadystate is reached
    // less MutationObserver churn
    document.addEventListener('readystatechange', function() {
      if (document.readyState === 'complete') {
        registerScopes();
      }
    });
  }
})(window.PointerGestures);

// Copyright (c) 2014 The Polymer Project Authors. All rights reserved.
// This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
// The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
// The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
// Code distributed by Google as part of the polymer project is also
// subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt

(function(global) {
  'use strict';

  var filter = Array.prototype.filter.call.bind(Array.prototype.filter);

  function getTreeScope(node) {
    while (node.parentNode) {
      node = node.parentNode;
    }

    return typeof node.getElementById === 'function' ? node : null;
  }

  Node.prototype.bind = function(name, observable) {
    console.error('Unhandled binding to Node: ', this, name, observable);
  };

  function updateBindings(node, name, binding) {
    var bindings = node.bindings_;
    if (!bindings)
      bindings = node.bindings_ = {};

    if (bindings[name])
      binding[name].close();

    return bindings[name] = binding;
  }

  function returnBinding(node, name, binding) {
    return binding;
  }

  function sanitizeValue(value) {
    return value == null ? '' : value;
  }

  function updateText(node, value) {
    node.data = sanitizeValue(value);
  }

  function textBinding(node) {
    return function(value) {
      return updateText(node, value);
    };
  }

  var maybeUpdateBindings = returnBinding;

  Object.defineProperty(Platform, 'enableBindingsReflection', {
    get: function() {
      return maybeUpdateBindings === updateBindings;
    },
    set: function(enable) {
      maybeUpdateBindings = enable ? updateBindings : returnBinding;
      return enable;
    },
    configurable: true
  });

  Text.prototype.bind = function(name, value, oneTime) {
    if (name !== 'textContent')
      return Node.prototype.bind.call(this, name, value, oneTime);

    if (oneTime)
      return updateText(this, value);

    var observable = value;
    updateText(this, observable.open(textBinding(this)));
    return maybeUpdateBindings(this, name, observable);
  }

  function updateAttribute(el, name, conditional, value) {
    if (conditional) {
      if (value)
        el.setAttribute(name, '');
      else
        el.removeAttribute(name);
      return;
    }

    el.setAttribute(name, sanitizeValue(value));
  }

  function attributeBinding(el, name, conditional) {
    return function(value) {
      updateAttribute(el, name, conditional, value);
    };
  }

  Element.prototype.bind = function(name, value, oneTime) {
    var conditional = name[name.length - 1] == '?';
    if (conditional) {
      this.removeAttribute(name);
      name = name.slice(0, -1);
    }

    if (oneTime)
      return updateAttribute(this, name, conditional, value);


    var observable = value;
    updateAttribute(this, name, conditional,
        observable.open(attributeBinding(this, name, conditional)));

    return maybeUpdateBindings(this, name, observable);
  };

  var checkboxEventType;
  (function() {
    // Attempt to feature-detect which event (change or click) is fired first
    // for checkboxes.
    var div = document.createElement('div');
    var checkbox = div.appendChild(document.createElement('input'));
    checkbox.setAttribute('type', 'checkbox');
    var first;
    var count = 0;
    checkbox.addEventListener('click', function(e) {
      count++;
      first = first || 'click';
    });
    checkbox.addEventListener('change', function() {
      count++;
      first = first || 'change';
    });

    var event = document.createEvent('MouseEvent');
    event.initMouseEvent("click", true, true, window, 0, 0, 0, 0, 0, false,
        false, false, false, 0, null);
    checkbox.dispatchEvent(event);
    // WebKit/Blink don't fire the change event if the element is outside the
    // document, so assume 'change' for that case.
    checkboxEventType = count == 1 ? 'change' : first;
  })();

  function getEventForInputType(element) {
    switch (element.type) {
      case 'checkbox':
        return checkboxEventType;
      case 'radio':
      case 'select-multiple':
      case 'select-one':
        return 'change';
      case 'range':
        if (/Trident|MSIE/.test(navigator.userAgent))
          return 'change';
      default:
        return 'input';
    }
  }

  function updateInput(input, property, value, santizeFn) {
    input[property] = (santizeFn || sanitizeValue)(value);
  }

  function inputBinding(input, property, santizeFn) {
    return function(value) {
      return updateInput(input, property, value, santizeFn);
    }
  }

  function noop() {}

  function bindInputEvent(input, property, observable, postEventFn) {
    var eventType = getEventForInputType(input);

    function eventHandler() {
      observable.setValue(input[property]);
      observable.discardChanges();
      (postEventFn || noop)(input);
      Platform.performMicrotaskCheckpoint();
    }
    input.addEventListener(eventType, eventHandler);

    return {
      close: function() {
        input.removeEventListener(eventType, eventHandler);
        observable.close();
      },

      observable_: observable
    }
  }

  function booleanSanitize(value) {
    return Boolean(value);
  }

  // |element| is assumed to be an HTMLInputElement with |type| == 'radio'.
  // Returns an array containing all radio buttons other than |element| that
  // have the same |name|, either in the form that |element| belongs to or,
  // if no form, in the document tree to which |element| belongs.
  //
  // This implementation is based upon the HTML spec definition of a
  // "radio button group":
  //   http://www.whatwg.org/specs/web-apps/current-work/multipage/number-state.html#radio-button-group
  //
  function getAssociatedRadioButtons(element) {
    if (element.form) {
      return filter(element.form.elements, function(el) {
        return el != element &&
            el.tagName == 'INPUT' &&
            el.type == 'radio' &&
            el.name == element.name;
      });
    } else {
      var treeScope = getTreeScope(element);
      if (!treeScope)
        return [];
      var radios = treeScope.querySelectorAll(
          'input[type="radio"][name="' + element.name + '"]');
      return filter(radios, function(el) {
        return el != element && !el.form;
      });
    }
  }

  function checkedPostEvent(input) {
    // Only the radio button that is getting checked gets an event. We
    // therefore find all the associated radio buttons and update their
    // check binding manually.
    if (input.tagName === 'INPUT' &&
        input.type === 'radio') {
      getAssociatedRadioButtons(input).forEach(function(radio) {
        var checkedBinding = radio.bindings_.checked;
        if (checkedBinding) {
          // Set the value directly to avoid an infinite call stack.
          checkedBinding.observable_.setValue(false);
        }
      });
    }
  }

  HTMLInputElement.prototype.bind = function(name, value, oneTime) {
    if (name !== 'value' && name !== 'checked')
      return HTMLElement.prototype.bind.call(this, name, value, oneTime);

    this.removeAttribute(name);
    var sanitizeFn = name == 'checked' ? booleanSanitize : sanitizeValue;
    var postEventFn = name == 'checked' ? checkedPostEvent : noop;

    if (oneTime)
      return updateInput(this, name, value, sanitizeFn);


    var observable = value;
    var binding = bindInputEvent(this, name, observable, postEventFn);
    updateInput(this, name,
                observable.open(inputBinding(this, name, sanitizeFn)),
                sanitizeFn);

    // Checkboxes may need to update bindings of other checkboxes.
    return updateBindings(this, name, binding);
  }

  HTMLTextAreaElement.prototype.bind = function(name, value, oneTime) {
    if (name !== 'value')
      return HTMLElement.prototype.bind.call(this, name, value, oneTime);

    this.removeAttribute('value');

    if (oneTime)
      return updateInput(this, 'value', value);

    var observable = value;
    var binding = bindInputEvent(this, 'value', observable);
    updateInput(this, 'value',
                observable.open(inputBinding(this, 'value', sanitizeValue)));
    return maybeUpdateBindings(this, name, binding);
  }

  function updateOption(option, value) {
    var parentNode = option.parentNode;;
    var select;
    var selectBinding;
    var oldValue;
    if (parentNode instanceof HTMLSelectElement &&
        parentNode.bindings_ &&
        parentNode.bindings_.value) {
      select = parentNode;
      selectBinding = select.bindings_.value;
      oldValue = select.value;
    }

    option.value = sanitizeValue(value);

    if (select && select.value != oldValue) {
      selectBinding.observable_.setValue(select.value);
      selectBinding.observable_.discardChanges();
      Platform.performMicrotaskCheckpoint();
    }
  }

  function optionBinding(option) {
    return function(value) {
      updateOption(option, value);
    }
  }

  HTMLOptionElement.prototype.bind = function(name, value, oneTime) {
    if (name !== 'value')
      return HTMLElement.prototype.bind.call(this, name, value, oneTime);

    this.removeAttribute('value');

    if (oneTime)
      return updateOption(this, value);

    var observable = value;
    var binding = bindInputEvent(this, 'value', observable);
    updateOption(this, observable.open(optionBinding(this)));
    return maybeUpdateBindings(this, name, binding);
  }

  HTMLSelectElement.prototype.bind = function(name, value, oneTime) {
    if (name === 'selectedindex')
      name = 'selectedIndex';

    if (name !== 'selectedIndex' && name !== 'value')
      return HTMLElement.prototype.bind.call(this, name, value, oneTime);

    this.removeAttribute(name);

    if (oneTime)
      return updateInput(this, name, value);

    var observable = value;
    var binding = bindInputEvent(this, name, observable);
    updateInput(this, name,
                observable.open(inputBinding(this, name)));

    // Option update events may need to access select bindings.
    return updateBindings(this, name, binding);
  }
})(this);

// Copyright (c) 2014 The Polymer Project Authors. All rights reserved.
// This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
// The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
// The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
// Code distributed by Google as part of the polymer project is also
// subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt

(function(global) {
  'use strict';

  function assert(v) {
    if (!v)
      throw new Error('Assertion failed');
  }

  var forEach = Array.prototype.forEach.call.bind(Array.prototype.forEach);

  function getFragmentRoot(node) {
    var p;
    while (p = node.parentNode) {
      node = p;
    }

    return node;
  }

  function searchRefId(node, id) {
    if (!id)
      return;

    var ref;
    var selector = '#' + id;
    while (!ref) {
      node = getFragmentRoot(node);

      if (node.protoContent_)
        ref = node.protoContent_.querySelector(selector);
      else if (node.getElementById)
        ref = node.getElementById(id);

      if (ref || !node.templateCreator_)
        break

      node = node.templateCreator_;
    }

    return ref;
  }

  function getInstanceRoot(node) {
    while (node.parentNode) {
      node = node.parentNode;
    }
    return node.templateCreator_ ? node : null;
  }

  var Map;
  if (global.Map && typeof global.Map.prototype.forEach === 'function') {
    Map = global.Map;
  } else {
    Map = function() {
      this.keys = [];
      this.values = [];
    };

    Map.prototype = {
      set: function(key, value) {
        var index = this.keys.indexOf(key);
        if (index < 0) {
          this.keys.push(key);
          this.values.push(value);
        } else {
          this.values[index] = value;
        }
      },

      get: function(key) {
        var index = this.keys.indexOf(key);
        if (index < 0)
          return;

        return this.values[index];
      },

      delete: function(key, value) {
        var index = this.keys.indexOf(key);
        if (index < 0)
          return false;

        this.keys.splice(index, 1);
        this.values.splice(index, 1);
        return true;
      },

      forEach: function(f, opt_this) {
        for (var i = 0; i < this.keys.length; i++)
          f.call(opt_this || this, this.values[i], this.keys[i], this);
      }
    };
  }

  // JScript does not have __proto__. We wrap all object literals with
  // createObject which uses Object.create, Object.defineProperty and
  // Object.getOwnPropertyDescriptor to create a new object that does the exact
  // same thing. The main downside to this solution is that we have to extract
  // all those property descriptors for IE.
  var createObject = ('__proto__' in {}) ?
      function(obj) { return obj; } :
      function(obj) {
        var proto = obj.__proto__;
        if (!proto)
          return obj;
        var newObject = Object.create(proto);
        Object.getOwnPropertyNames(obj).forEach(function(name) {
          Object.defineProperty(newObject, name,
                               Object.getOwnPropertyDescriptor(obj, name));
        });
        return newObject;
      };

  // IE does not support have Document.prototype.contains.
  if (typeof document.contains != 'function') {
    Document.prototype.contains = function(node) {
      if (node === this || node.parentNode === this)
        return true;
      return this.documentElement.contains(node);
    }
  }

  var BIND = 'bind';
  var REPEAT = 'repeat';
  var IF = 'if';

  var templateAttributeDirectives = {
    'template': true,
    'repeat': true,
    'bind': true,
    'ref': true
  };

  var semanticTemplateElements = {
    'THEAD': true,
    'TBODY': true,
    'TFOOT': true,
    'TH': true,
    'TR': true,
    'TD': true,
    'COLGROUP': true,
    'COL': true,
    'CAPTION': true,
    'OPTION': true,
    'OPTGROUP': true
  };

  var hasTemplateElement = typeof HTMLTemplateElement !== 'undefined';
  if (hasTemplateElement) {
    // TODO(rafaelw): Remove when fix for
    // https://codereview.chromium.org/164803002/
    // makes it to Chrome release.
    (function() {
      var t = document.createElement('template');
      var d = t.content.ownerDocument;
      var html = d.appendChild(d.createElement('html'));
      var head = html.appendChild(d.createElement('head'));
      var base = d.createElement('base');
      base.href = document.baseURI;
      head.appendChild(base);
    })();
  }

  var allTemplatesSelectors = 'template, ' +
      Object.keys(semanticTemplateElements).map(function(tagName) {
        return tagName.toLowerCase() + '[template]';
      }).join(', ');

  function isSVGTemplate(el) {
    return el.tagName == 'template' &&
           el.namespaceURI == 'http://www.w3.org/2000/svg';
  }

  function isHTMLTemplate(el) {
    return el.tagName == 'TEMPLATE' &&
           el.namespaceURI == 'http://www.w3.org/1999/xhtml';
  }

  function isAttributeTemplate(el) {
    return Boolean(semanticTemplateElements[el.tagName] &&
                   el.hasAttribute('template'));
  }

  function isTemplate(el) {
    if (el.isTemplate_ === undefined)
      el.isTemplate_ = el.tagName == 'TEMPLATE' || isAttributeTemplate(el);

    return el.isTemplate_;
  }

  // FIXME: Observe templates being added/removed from documents
  // FIXME: Expose imperative API to decorate and observe templates in
  // "disconnected tress" (e.g. ShadowRoot)
  document.addEventListener('DOMContentLoaded', function(e) {
    bootstrapTemplatesRecursivelyFrom(document);
    // FIXME: Is this needed? Seems like it shouldn't be.
    Platform.performMicrotaskCheckpoint();
  }, false);

  function forAllTemplatesFrom(node, fn) {
    var subTemplates = node.querySelectorAll(allTemplatesSelectors);

    if (isTemplate(node))
      fn(node)
    forEach(subTemplates, fn);
  }

  function bootstrapTemplatesRecursivelyFrom(node) {
    function bootstrap(template) {
      if (!HTMLTemplateElement.decorate(template))
        bootstrapTemplatesRecursivelyFrom(template.content);
    }

    forAllTemplatesFrom(node, bootstrap);
  }

  if (!hasTemplateElement) {
    /**
     * This represents a <template> element.
     * @constructor
     * @extends {HTMLElement}
     */
    global.HTMLTemplateElement = function() {
      throw TypeError('Illegal constructor');
    };
  }

  var hasProto = '__proto__' in {};

  function mixin(to, from) {
    Object.getOwnPropertyNames(from).forEach(function(name) {
      Object.defineProperty(to, name,
                            Object.getOwnPropertyDescriptor(from, name));
    });
  }

  // http://dvcs.w3.org/hg/webcomponents/raw-file/tip/spec/templates/index.html#dfn-template-contents-owner
  function getOrCreateTemplateContentsOwner(template) {
    var doc = template.ownerDocument
    if (!doc.defaultView)
      return doc;
    var d = doc.templateContentsOwner_;
    if (!d) {
      // TODO(arv): This should either be a Document or HTMLDocument depending
      // on doc.
      d = doc.implementation.createHTMLDocument('');
      while (d.lastChild) {
        d.removeChild(d.lastChild);
      }
      doc.templateContentsOwner_ = d;
    }
    return d;
  }

  function getTemplateStagingDocument(template) {
    if (!template.stagingDocument_) {
      var owner = template.ownerDocument;
      if (!owner.stagingDocument_) {
        owner.stagingDocument_ = owner.implementation.createHTMLDocument('');

        // TODO(rafaelw): Remove when fix for
        // https://codereview.chromium.org/164803002/
        // makes it to Chrome release.
        var base = owner.stagingDocument_.createElement('base');
        base.href = document.baseURI;
        owner.stagingDocument_.head.appendChild(base);

        owner.stagingDocument_.stagingDocument_ = owner.stagingDocument_;
      }

      template.stagingDocument_ = owner.stagingDocument_;
    }

    return template.stagingDocument_;
  }

  // For non-template browsers, the parser will disallow <template> in certain
  // locations, so we allow "attribute templates" which combine the template
  // element with the top-level container node of the content, e.g.
  //
  //   <tr template repeat="{{ foo }}"" class="bar"><td>Bar</td></tr>
  //
  // becomes
  //
  //   <template repeat="{{ foo }}">
  //   + #document-fragment
  //     + <tr class="bar">
  //       + <td>Bar</td>
  //
  function extractTemplateFromAttributeTemplate(el) {
    var template = el.ownerDocument.createElement('template');
    el.parentNode.insertBefore(template, el);

    var attribs = el.attributes;
    var count = attribs.length;
    while (count-- > 0) {
      var attrib = attribs[count];
      if (templateAttributeDirectives[attrib.name]) {
        if (attrib.name !== 'template')
          template.setAttribute(attrib.name, attrib.value);
        el.removeAttribute(attrib.name);
      }
    }

    return template;
  }

  function extractTemplateFromSVGTemplate(el) {
    var template = el.ownerDocument.createElement('template');
    el.parentNode.insertBefore(template, el);

    var attribs = el.attributes;
    var count = attribs.length;
    while (count-- > 0) {
      var attrib = attribs[count];
      template.setAttribute(attrib.name, attrib.value);
      el.removeAttribute(attrib.name);
    }

    el.parentNode.removeChild(el);
    return template;
  }

  function liftNonNativeTemplateChildrenIntoContent(template, el, useRoot) {
    var content = template.content;
    if (useRoot) {
      content.appendChild(el);
      return;
    }

    var child;
    while (child = el.firstChild) {
      content.appendChild(child);
    }
  }

  var templateObserver;
  if (typeof MutationObserver == 'function') {
    templateObserver = new MutationObserver(function(records) {
      for (var i = 0; i < records.length; i++) {
        records[i].target.refChanged_();
      }
    });
  }

  /**
   * Ensures proper API and content model for template elements.
   * @param {HTMLTemplateElement} opt_instanceRef The template element which
   *     |el| template element will return as the value of its ref(), and whose
   *     content will be used as source when createInstance() is invoked.
   */
  HTMLTemplateElement.decorate = function(el, opt_instanceRef) {
    if (el.templateIsDecorated_)
      return false;

    var templateElement = el;
    templateElement.templateIsDecorated_ = true;

    var isNativeHTMLTemplate = isHTMLTemplate(templateElement) &&
                               hasTemplateElement;
    var bootstrapContents = isNativeHTMLTemplate;
    var liftContents = !isNativeHTMLTemplate;
    var liftRoot = false;

    if (!isNativeHTMLTemplate) {
      if (isAttributeTemplate(templateElement)) {
        assert(!opt_instanceRef);
        templateElement = extractTemplateFromAttributeTemplate(el);
        templateElement.templateIsDecorated_ = true;
        isNativeHTMLTemplate = hasTemplateElement;
        liftRoot = true;
      } else if (isSVGTemplate(templateElement)) {
        templateElement = extractTemplateFromSVGTemplate(el);
        templateElement.templateIsDecorated_ = true;
        isNativeHTMLTemplate = hasTemplateElement;
      }
    }

    if (!isNativeHTMLTemplate) {
      fixTemplateElementPrototype(templateElement);
      var doc = getOrCreateTemplateContentsOwner(templateElement);
      templateElement.content_ = doc.createDocumentFragment();
    }

    if (opt_instanceRef) {
      // template is contained within an instance, its direct content must be
      // empty
      templateElement.instanceRef_ = opt_instanceRef;
    } else if (liftContents) {
      liftNonNativeTemplateChildrenIntoContent(templateElement,
                                               el,
                                               liftRoot);
    } else if (bootstrapContents) {
      bootstrapTemplatesRecursivelyFrom(templateElement.content);
    }

    return true;
  };

  // TODO(rafaelw): This used to decorate recursively all templates from a given
  // node. This happens by default on 'DOMContentLoaded', but may be needed
  // in subtrees not descendent from document (e.g. ShadowRoot).
  // Review whether this is the right public API.
  HTMLTemplateElement.bootstrap = bootstrapTemplatesRecursivelyFrom;

  var htmlElement = global.HTMLUnknownElement || HTMLElement;

  var contentDescriptor = {
    get: function() {
      return this.content_;
    },
    enumerable: true,
    configurable: true
  };

  if (!hasTemplateElement) {
    // Gecko is more picky with the prototype than WebKit. Make sure to use the
    // same prototype as created in the constructor.
    HTMLTemplateElement.prototype = Object.create(htmlElement.prototype);

    Object.defineProperty(HTMLTemplateElement.prototype, 'content',
                          contentDescriptor);
  }

  function fixTemplateElementPrototype(el) {
    if (hasProto)
      el.__proto__ = HTMLTemplateElement.prototype;
    else
      mixin(el, HTMLTemplateElement.prototype);
  }

  function ensureSetModelScheduled(template) {
    if (!template.setModelFn_) {
      template.setModelFn_ = function() {
        template.setModelFnScheduled_ = false;
        var map = getBindings(template,
            template.delegate_ && template.delegate_.prepareBinding);
        processBindings(template, map, template.model_);
      };
    }

    if (!template.setModelFnScheduled_) {
      template.setModelFnScheduled_ = true;
      Observer.runEOM_(template.setModelFn_);
    }
  }

  mixin(HTMLTemplateElement.prototype, {
    bind: function(name, value, oneTime) {
      if (name != 'ref')
        return Element.prototype.bind.call(this, name, value, oneTime);

      var self = this;
      var ref = oneTime ? value : value.open(function(ref) {
        self.setAttribute('ref', ref);
        self.refChanged_();
      });

      this.setAttribute('ref', ref);
      this.refChanged_();
      if (oneTime)
        return;

      if (!this.bindings_) {
        this.bindings_ = { ref: value };
      } else {
        this.bindings_.ref = value;
      }

      return value;
    },

    processBindingDirectives_: function(directives) {
      if (this.iterator_)
        this.iterator_.closeDeps();

      if (!directives.if && !directives.bind && !directives.repeat) {
        if (this.iterator_) {
          this.iterator_.close();
          this.iterator_ = undefined;
        }

        return;
      }

      if (!this.iterator_) {
        this.iterator_ = new TemplateIterator(this);
      }

      this.iterator_.updateDependencies(directives, this.model_);

      if (templateObserver) {
        templateObserver.observe(this, { attributes: true,
                                         attributeFilter: ['ref'] });
      }

      return this.iterator_;
    },

    createInstance: function(model, bindingDelegate, delegate_) {
      if (bindingDelegate)
        delegate_ = this.newDelegate_(bindingDelegate);

      if (!this.refContent_)
        this.refContent_ = this.ref_.content;
      var content = this.refContent_;
      if (content.firstChild === null)
        return emptyInstance;

      var map = this.bindingMap_;
      if (!map || map.content !== content) {
        // TODO(rafaelw): Setup a MutationObserver on content to detect
        // when the instanceMap is invalid.
        map = createInstanceBindingMap(content,
            delegate_ && delegate_.prepareBinding) || [];
        map.content = content;
        this.bindingMap_ = map;
      }

      var stagingDocument = getTemplateStagingDocument(this);
      var instance = stagingDocument.createDocumentFragment();
      instance.templateCreator_ = this;
      instance.protoContent_ = content;
      instance.bindings_ = [];
      instance.terminator_ = null;
      var instanceRecord = instance.templateInstance_ = {
        firstNode: null,
        lastNode: null,
        model: model
      };

      var i = 0;
      var collectTerminator = false;
      for (var child = content.firstChild; child; child = child.nextSibling) {
        // The terminator of the instance is the clone of the last child of the
        // content. If the last child is an active template, it may produce
        // instances as a result of production, so simply collecting the last
        // child of the instance after it has finished producing may be wrong.
        if (child.nextSibling === null)
          collectTerminator = true;

        var clone = cloneAndBindInstance(child, instance, stagingDocument,
                                         map.children[i++],
                                         model,
                                         delegate_,
                                         instance.bindings_);
        clone.templateInstance_ = instanceRecord;
        if (collectTerminator)
          instance.terminator_ = clone;
      }

      instanceRecord.firstNode = instance.firstChild;
      instanceRecord.lastNode = instance.lastChild;
      instance.templateCreator_ = undefined;
      instance.protoContent_ = undefined;
      return instance;
    },

    get model() {
      return this.model_;
    },

    set model(model) {
      this.model_ = model;
      ensureSetModelScheduled(this);
    },

    get bindingDelegate() {
      return this.delegate_ && this.delegate_.raw;
    },

    refChanged_: function() {
      if (!this.iterator_ || this.refContent_ === this.ref_.content)
        return;

      this.refContent_ = undefined;
      this.iterator_.valueChanged();
      this.iterator_.updateIteratedValue();
    },

    clear: function() {
      this.model_ = undefined;
      this.delegate_ = undefined;
      if (this.bindings_ && this.bindings_.ref)
        this.bindings_.ref.close()
      this.refContent_ = undefined;
      if (!this.iterator_)
        return;
      this.iterator_.valueChanged();
      this.iterator_.close()
      this.iterator_ = undefined;
    },

    setDelegate_: function(delegate) {
      this.delegate_ = delegate;
      this.bindingMap_ = undefined;
      if (this.iterator_) {
        this.iterator_.instancePositionChangedFn_ = undefined;
        this.iterator_.instanceModelFn_ = undefined;
      }
    },

    newDelegate_: function(bindingDelegate) {
      if (!bindingDelegate)
        return {};

      function delegateFn(name) {
        var fn = bindingDelegate && bindingDelegate[name];
        if (typeof fn != 'function')
          return;

        return function() {
          return fn.apply(bindingDelegate, arguments);
        };
      }

      return {
        raw: bindingDelegate,
        prepareBinding: delegateFn('prepareBinding'),
        prepareInstanceModel: delegateFn('prepareInstanceModel'),
        prepareInstancePositionChanged:
            delegateFn('prepareInstancePositionChanged')
      };
    },

    // TODO(rafaelw): Assigning .bindingDelegate always succeeds. It may
    // make sense to issue a warning or even throw if the template is already
    // "activated", since this would be a strange thing to do.
    set bindingDelegate(bindingDelegate) {
      if (this.delegate_) {
        throw Error('Template must be cleared before a new bindingDelegate ' +
                    'can be assigned');
      }

      this.setDelegate_(this.newDelegate_(bindingDelegate));
    },

    get ref_() {
      var ref = searchRefId(this, this.getAttribute('ref'));
      if (!ref)
        ref = this.instanceRef_;

      if (!ref)
        return this;

      var nextRef = ref.ref_;
      return nextRef ? nextRef : ref;
    }
  });

  // Returns
  //   a) undefined if there are no mustaches.
  //   b) [TEXT, (ONE_TIME?, PATH, DELEGATE_FN, TEXT)+] if there is at least one mustache.
  function parseMustaches(s, name, node, prepareBindingFn) {
    if (!s || !s.length)
      return;

    var tokens;
    var length = s.length;
    var startIndex = 0, lastIndex = 0, endIndex = 0;
    var onlyOneTime = true;
    while (lastIndex < length) {
      var startIndex = s.indexOf('{{', lastIndex);
      var oneTimeStart = s.indexOf('[[', lastIndex);
      var oneTime = false;
      var terminator = '}}';

      if (oneTimeStart >= 0 &&
          (startIndex < 0 || oneTimeStart < startIndex)) {
        startIndex = oneTimeStart;
        oneTime = true;
        terminator = ']]';
      }

      endIndex = startIndex < 0 ? -1 : s.indexOf(terminator, startIndex + 2);

      if (endIndex < 0) {
        if (!tokens)
          return;

        tokens.push(s.slice(lastIndex)); // TEXT
        break;
      }

      tokens = tokens || [];
      tokens.push(s.slice(lastIndex, startIndex)); // TEXT
      var pathString = s.slice(startIndex + 2, endIndex).trim();
      tokens.push(oneTime); // ONE_TIME?
      onlyOneTime = onlyOneTime && oneTime;
      var delegateFn = prepareBindingFn &&
                       prepareBindingFn(pathString, name, node);
      // Don't try to parse the expression if there's a prepareBinding function
      if (delegateFn == null) {
        tokens.push(Path.get(pathString)); // PATH
      } else {
        tokens.push(null);
      }
      tokens.push(delegateFn); // DELEGATE_FN
      lastIndex = endIndex + 2;
    }

    if (lastIndex === length)
      tokens.push(''); // TEXT

    tokens.hasOnePath = tokens.length === 5;
    tokens.isSimplePath = tokens.hasOnePath &&
                          tokens[0] == '' &&
                          tokens[4] == '';
    tokens.onlyOneTime = onlyOneTime;

    tokens.combinator = function(values) {
      var newValue = tokens[0];

      for (var i = 1; i < tokens.length; i += 4) {
        var value = tokens.hasOnePath ? values : values[(i - 1) / 4];
        if (value !== undefined)
          newValue += value;
        newValue += tokens[i + 3];
      }

      return newValue;
    }

    return tokens;
  };

  function processOneTimeBinding(name, tokens, node, model) {
    if (tokens.hasOnePath) {
      var delegateFn = tokens[3];
      var value = delegateFn ? delegateFn(model, node, true) :
                               tokens[2].getValueFrom(model);
      return tokens.isSimplePath ? value : tokens.combinator(value);
    }

    var values = [];
    for (var i = 1; i < tokens.length; i += 4) {
      var delegateFn = tokens[i + 2];
      values[(i - 1) / 4] = delegateFn ? delegateFn(model, node) :
          tokens[i + 1].getValueFrom(model);
    }

    return tokens.combinator(values);
  }

  function processSinglePathBinding(name, tokens, node, model) {
    var delegateFn = tokens[3];
    var observer = delegateFn ? delegateFn(model, node, false) :
        new PathObserver(model, tokens[2]);

    return tokens.isSimplePath ? observer :
        new ObserverTransform(observer, tokens.combinator);
  }

  function processBinding(name, tokens, node, model) {
    if (tokens.onlyOneTime)
      return processOneTimeBinding(name, tokens, node, model);

    if (tokens.hasOnePath)
      return processSinglePathBinding(name, tokens, node, model);

    var observer = new CompoundObserver();

    for (var i = 1; i < tokens.length; i += 4) {
      var oneTime = tokens[i];
      var delegateFn = tokens[i + 2];

      if (delegateFn) {
        var value = delegateFn(model, node, oneTime);
        if (oneTime)
          observer.addPath(value)
        else
          observer.addObserver(value);
        continue;
      }

      var path = tokens[i + 1];
      if (oneTime)
        observer.addPath(path.getValueFrom(model))
      else
        observer.addPath(model, path);
    }

    return new ObserverTransform(observer, tokens.combinator);
  }

  function processBindings(node, bindings, model, instanceBindings) {
    for (var i = 0; i < bindings.length; i += 2) {
      var name = bindings[i]
      var tokens = bindings[i + 1];
      var value = processBinding(name, tokens, node, model);
      var binding = node.bind(name, value, tokens.onlyOneTime);
      if (binding && instanceBindings)
        instanceBindings.push(binding);
    }

    if (!bindings.isTemplate)
      return;

    node.model_ = model;
    var iter = node.processBindingDirectives_(bindings);
    if (instanceBindings && iter)
      instanceBindings.push(iter);
  }

  function parseWithDefault(el, name, prepareBindingFn) {
    var v = el.getAttribute(name);
    return parseMustaches(v == '' ? '{{}}' : v, name, el, prepareBindingFn);
  }

  function parseAttributeBindings(element, prepareBindingFn) {
    assert(element);

    var bindings = [];
    var ifFound = false;
    var bindFound = false;

    for (var i = 0; i < element.attributes.length; i++) {
      var attr = element.attributes[i];
      var name = attr.name;
      var value = attr.value;

      // Allow bindings expressed in attributes to be prefixed with underbars.
      // We do this to allow correct semantics for browsers that don't implement
      // <template> where certain attributes might trigger side-effects -- and
      // for IE which sanitizes certain attributes, disallowing mustache
      // replacements in their text.
      while (name[0] === '_') {
        name = name.substring(1);
      }

      if (isTemplate(element) &&
          (name === IF || name === BIND || name === REPEAT)) {
        continue;
      }

      var tokens = parseMustaches(value, name, element,
                                  prepareBindingFn);
      if (!tokens)
        continue;

      bindings.push(name, tokens);
    }

    if (isTemplate(element)) {
      bindings.isTemplate = true;
      bindings.if = parseWithDefault(element, IF, prepareBindingFn);
      bindings.bind = parseWithDefault(element, BIND, prepareBindingFn);
      bindings.repeat = parseWithDefault(element, REPEAT, prepareBindingFn);

      if (bindings.if && !bindings.bind && !bindings.repeat)
        bindings.bind = parseMustaches('{{}}', BIND, element, prepareBindingFn);
    }

    return bindings;
  }

  function getBindings(node, prepareBindingFn) {
    if (node.nodeType === Node.ELEMENT_NODE)
      return parseAttributeBindings(node, prepareBindingFn);

    if (node.nodeType === Node.TEXT_NODE) {
      var tokens = parseMustaches(node.data, 'textContent', node,
                                  prepareBindingFn);
      if (tokens)
        return ['textContent', tokens];
    }

    return [];
  }

  function cloneAndBindInstance(node, parent, stagingDocument, bindings, model,
                                delegate,
                                instanceBindings,
                                instanceRecord) {
    var clone = parent.appendChild(stagingDocument.importNode(node, false));

    var i = 0;
    for (var child = node.firstChild; child; child = child.nextSibling) {
      cloneAndBindInstance(child, clone, stagingDocument,
                            bindings.children[i++],
                            model,
                            delegate,
                            instanceBindings);
    }

    if (bindings.isTemplate) {
      HTMLTemplateElement.decorate(clone, node);
      if (delegate)
        clone.setDelegate_(delegate);
    }

    processBindings(clone, bindings, model, instanceBindings);
    return clone;
  }

  function createInstanceBindingMap(node, prepareBindingFn) {
    var map = getBindings(node, prepareBindingFn);
    map.children = {};
    var index = 0;
    for (var child = node.firstChild; child; child = child.nextSibling) {
      map.children[index++] = createInstanceBindingMap(child, prepareBindingFn);
    }

    return map;
  }

  Object.defineProperty(Node.prototype, 'templateInstance', {
    get: function() {
      var instance = this.templateInstance_;
      return instance ? instance :
          (this.parentNode ? this.parentNode.templateInstance : undefined);
    }
  });

  var emptyInstance = document.createDocumentFragment();
  emptyInstance.bindings_ = [];
  emptyInstance.terminator_ = null;

  function TemplateIterator(templateElement) {
    this.closed = false;
    this.templateElement_ = templateElement;
    this.instances = [];
    this.deps = undefined;
    this.iteratedValue = [];
    this.presentValue = undefined;
    this.arrayObserver = undefined;
  }

  TemplateIterator.prototype = {
    closeDeps: function() {
      var deps = this.deps;
      if (deps) {
        if (deps.ifOneTime === false)
          deps.ifValue.close();
        if (deps.oneTime === false)
          deps.value.close();
      }
    },

    updateDependencies: function(directives, model) {
      this.closeDeps();

      var deps = this.deps = {};
      var template = this.templateElement_;

      if (directives.if) {
        deps.hasIf = true;
        deps.ifOneTime = directives.if.onlyOneTime;
        deps.ifValue = processBinding(IF, directives.if, template, model);

        // oneTime if & predicate is false. nothing else to do.
        if (deps.ifOneTime && !deps.ifValue) {
          this.updateIteratedValue();
          return;
        }

        if (!deps.ifOneTime)
          deps.ifValue.open(this.updateIteratedValue, this);
      }

      if (directives.repeat) {
        deps.repeat = true;
        deps.oneTime = directives.repeat.onlyOneTime;
        deps.value = processBinding(REPEAT, directives.repeat, template, model);
      } else {
        deps.repeat = false;
        deps.oneTime = directives.bind.onlyOneTime;
        deps.value = processBinding(BIND, directives.bind, template, model);
      }

      if (!deps.oneTime)
        deps.value.open(this.updateIteratedValue, this);

      this.updateIteratedValue();
    },

    updateIteratedValue: function() {
      if (this.deps.hasIf) {
        var ifValue = this.deps.ifValue;
        if (!this.deps.ifOneTime)
          ifValue = ifValue.discardChanges();
        if (!ifValue) {
          this.valueChanged();
          return;
        }
      }

      var value = this.deps.value;
      if (!this.deps.oneTime)
        value = value.discardChanges();
      if (!this.deps.repeat)
        value = [value];
      var observe = this.deps.repeat &&
                    !this.deps.oneTime &&
                    Array.isArray(value);
      this.valueChanged(value, observe);
    },

    valueChanged: function(value, observeValue) {
      if (!Array.isArray(value))
        value = [];

      if (value === this.iteratedValue)
        return;

      this.unobserve();
      this.presentValue = value;
      if (observeValue) {
        this.arrayObserver = new ArrayObserver(this.presentValue);
        this.arrayObserver.open(this.handleSplices, this);
      }

      this.handleSplices(ArrayObserver.calculateSplices(this.presentValue,
                                                        this.iteratedValue));
    },

    getLastInstanceNode: function(index) {
      if (index == -1)
        return this.templateElement_;
      var instance = this.instances[index];
      var terminator = instance.terminator_;
      if (!terminator)
        return this.getLastInstanceNode(index - 1);

      if (terminator.nodeType !== Node.ELEMENT_NODE ||
          this.templateElement_ === terminator) {
        return terminator;
      }

      var subtemplateIterator = terminator.iterator_;
      if (!subtemplateIterator)
        return terminator;

      return subtemplateIterator.getLastTemplateNode();
    },

    getLastTemplateNode: function() {
      return this.getLastInstanceNode(this.instances.length - 1);
    },

    insertInstanceAt: function(index, fragment) {
      var previousInstanceLast = this.getLastInstanceNode(index - 1);
      var parent = this.templateElement_.parentNode;
      this.instances.splice(index, 0, fragment);

      parent.insertBefore(fragment, previousInstanceLast.nextSibling);
    },

    extractInstanceAt: function(index) {
      var previousInstanceLast = this.getLastInstanceNode(index - 1);
      var lastNode = this.getLastInstanceNode(index);
      var parent = this.templateElement_.parentNode;
      var instance = this.instances.splice(index, 1)[0];

      while (lastNode !== previousInstanceLast) {
        var node = previousInstanceLast.nextSibling;
        if (node == lastNode)
          lastNode = previousInstanceLast;

        instance.appendChild(parent.removeChild(node));
      }

      return instance;
    },

    getDelegateFn: function(fn) {
      fn = fn && fn(this.templateElement_);
      return typeof fn === 'function' ? fn : null;
    },

    handleSplices: function(splices) {
      if (this.closed || !splices.length)
        return;

      var template = this.templateElement_;

      if (!template.parentNode) {
        this.close();
        return;
      }

      ArrayObserver.applySplices(this.iteratedValue, this.presentValue,
                                 splices);

      var delegate = template.delegate_;
      if (this.instanceModelFn_ === undefined) {
        this.instanceModelFn_ =
            this.getDelegateFn(delegate && delegate.prepareInstanceModel);
      }

      if (this.instancePositionChangedFn_ === undefined) {
        this.instancePositionChangedFn_ =
            this.getDelegateFn(delegate &&
                               delegate.prepareInstancePositionChanged);
      }

      // Instance Removals
      var instanceCache = new Map;
      var removeDelta = 0;
      for (var i = 0; i < splices.length; i++) {
        var splice = splices[i];
        var removed = splice.removed;
        for (var j = 0; j < removed.length; j++) {
          var model = removed[j];
          var instance = this.extractInstanceAt(splice.index + removeDelta);
          if (instance !== emptyInstance) {
            instanceCache.set(model, instance);
          }
        }

        removeDelta -= splice.addedCount;
      }

      // Instance Insertions
      for (var i = 0; i < splices.length; i++) {
        var splice = splices[i];
        var addIndex = splice.index;
        for (; addIndex < splice.index + splice.addedCount; addIndex++) {
          var model = this.iteratedValue[addIndex];
          var instance = instanceCache.get(model);
          if (instance) {
            instanceCache.delete(model);
          } else {
            if (this.instanceModelFn_) {
              model = this.instanceModelFn_(model);
            }

            if (model === undefined) {
              instance = emptyInstance;
            } else {
              instance = template.createInstance(model, undefined, delegate);
            }
          }

          this.insertInstanceAt(addIndex, instance);
        }
      }

      instanceCache.forEach(function(instance) {
        this.closeInstanceBindings(instance);
      }, this);

      if (this.instancePositionChangedFn_)
        this.reportInstancesMoved(splices);
    },

    reportInstanceMoved: function(index) {
      var instance = this.instances[index];
      if (instance === emptyInstance)
        return;

      this.instancePositionChangedFn_(instance.templateInstance_, index);
    },

    reportInstancesMoved: function(splices) {
      var index = 0;
      var offset = 0;
      for (var i = 0; i < splices.length; i++) {
        var splice = splices[i];
        if (offset != 0) {
          while (index < splice.index) {
            this.reportInstanceMoved(index);
            index++;
          }
        } else {
          index = splice.index;
        }

        while (index < splice.index + splice.addedCount) {
          this.reportInstanceMoved(index);
          index++;
        }

        offset += splice.addedCount - splice.removed.length;
      }

      if (offset == 0)
        return;

      var length = this.instances.length;
      while (index < length) {
        this.reportInstanceMoved(index);
        index++;
      }
    },

    closeInstanceBindings: function(instance) {
      var bindings = instance.bindings_;
      for (var i = 0; i < bindings.length; i++) {
        bindings[i].close();
      }
    },

    unobserve: function() {
      if (!this.arrayObserver)
        return;

      this.arrayObserver.close();
      this.arrayObserver = undefined;
    },

    close: function() {
      if (this.closed)
        return;
      this.unobserve();
      for (var i = 0; i < this.instances.length; i++) {
        this.closeInstanceBindings(this.instances[i]);
      }

      this.instances.length = 0;
      this.closeDeps();
      this.templateElement_.iterator_ = undefined;
      this.closed = true;
    }
  };

  // Polyfill-specific API.
  HTMLTemplateElement.forAllTemplatesFrom_ = forAllTemplatesFrom;
})(this);

/*
  Copyright (C) 2013 Ariya Hidayat <ariya.hidayat@gmail.com>
  Copyright (C) 2013 Thaddee Tyl <thaddee.tyl@gmail.com>
  Copyright (C) 2012 Ariya Hidayat <ariya.hidayat@gmail.com>
  Copyright (C) 2012 Mathias Bynens <mathias@qiwi.be>
  Copyright (C) 2012 Joost-Wim Boekesteijn <joost-wim@boekesteijn.nl>
  Copyright (C) 2012 Kris Kowal <kris.kowal@cixar.com>
  Copyright (C) 2012 Yusuke Suzuki <utatane.tea@gmail.com>
  Copyright (C) 2012 Arpad Borsos <arpad.borsos@googlemail.com>
  Copyright (C) 2011 Ariya Hidayat <ariya.hidayat@gmail.com>

  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions are met:

    * Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.
    * Redistributions in binary form must reproduce the above copyright
      notice, this list of conditions and the following disclaimer in the
      documentation and/or other materials provided with the distribution.

  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
  DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

(function (global) {
    'use strict';

    var Token,
        TokenName,
        Syntax,
        Messages,
        source,
        index,
        length,
        delegate,
        lookahead,
        state;

    Token = {
        BooleanLiteral: 1,
        EOF: 2,
        Identifier: 3,
        Keyword: 4,
        NullLiteral: 5,
        NumericLiteral: 6,
        Punctuator: 7,
        StringLiteral: 8
    };

    TokenName = {};
    TokenName[Token.BooleanLiteral] = 'Boolean';
    TokenName[Token.EOF] = '<end>';
    TokenName[Token.Identifier] = 'Identifier';
    TokenName[Token.Keyword] = 'Keyword';
    TokenName[Token.NullLiteral] = 'Null';
    TokenName[Token.NumericLiteral] = 'Numeric';
    TokenName[Token.Punctuator] = 'Punctuator';
    TokenName[Token.StringLiteral] = 'String';

    Syntax = {
        ArrayExpression: 'ArrayExpression',
        BinaryExpression: 'BinaryExpression',
        CallExpression: 'CallExpression',
        ConditionalExpression: 'ConditionalExpression',
        EmptyStatement: 'EmptyStatement',
        ExpressionStatement: 'ExpressionStatement',
        Identifier: 'Identifier',
        Literal: 'Literal',
        LabeledStatement: 'LabeledStatement',
        LogicalExpression: 'LogicalExpression',
        MemberExpression: 'MemberExpression',
        ObjectExpression: 'ObjectExpression',
        Program: 'Program',
        Property: 'Property',
        ThisExpression: 'ThisExpression',
        UnaryExpression: 'UnaryExpression'
    };

    // Error messages should be identical to V8.
    Messages = {
        UnexpectedToken:  'Unexpected token %0',
        UnknownLabel: 'Undefined label \'%0\'',
        Redeclaration: '%0 \'%1\' has already been declared'
    };

    // Ensure the condition is true, otherwise throw an error.
    // This is only to have a better contract semantic, i.e. another safety net
    // to catch a logic error. The condition shall be fulfilled in normal case.
    // Do NOT use this to enforce a certain condition on any user input.

    function assert(condition, message) {
        if (!condition) {
            throw new Error('ASSERT: ' + message);
        }
    }

    function isDecimalDigit(ch) {
        return (ch >= 48 && ch <= 57);   // 0..9
    }


    // 7.2 White Space

    function isWhiteSpace(ch) {
        return (ch === 32) ||  // space
            (ch === 9) ||      // tab
            (ch === 0xB) ||
            (ch === 0xC) ||
            (ch === 0xA0) ||
            (ch >= 0x1680 && '\u1680\u180E\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200A\u202F\u205F\u3000\uFEFF'.indexOf(String.fromCharCode(ch)) > 0);
    }

    // 7.3 Line Terminators

    function isLineTerminator(ch) {
        return (ch === 10) || (ch === 13) || (ch === 0x2028) || (ch === 0x2029);
    }

    // 7.6 Identifier Names and Identifiers

    function isIdentifierStart(ch) {
        return (ch === 36) || (ch === 95) ||  // $ (dollar) and _ (underscore)
            (ch >= 65 && ch <= 90) ||         // A..Z
            (ch >= 97 && ch <= 122);          // a..z
    }

    function isIdentifierPart(ch) {
        return (ch === 36) || (ch === 95) ||  // $ (dollar) and _ (underscore)
            (ch >= 65 && ch <= 90) ||         // A..Z
            (ch >= 97 && ch <= 122) ||        // a..z
            (ch >= 48 && ch <= 57);           // 0..9
    }

    // 7.6.1.1 Keywords

    function isKeyword(id) {
        return (id === 'this')
    }

    // 7.4 Comments

    function skipWhitespace() {
        while (index < length && isWhiteSpace(source.charCodeAt(index))) {
           ++index;
        }
    }

    function getIdentifier() {
        var start, ch;

        start = index++;
        while (index < length) {
            ch = source.charCodeAt(index);
            if (isIdentifierPart(ch)) {
                ++index;
            } else {
                break;
            }
        }

        return source.slice(start, index);
    }

    function scanIdentifier() {
        var start, id, type;

        start = index;

        id = getIdentifier();

        // There is no keyword or literal with only one character.
        // Thus, it must be an identifier.
        if (id.length === 1) {
            type = Token.Identifier;
        } else if (isKeyword(id)) {
            type = Token.Keyword;
        } else if (id === 'null') {
            type = Token.NullLiteral;
        } else if (id === 'true' || id === 'false') {
            type = Token.BooleanLiteral;
        } else {
            type = Token.Identifier;
        }

        return {
            type: type,
            value: id,
            range: [start, index]
        };
    }


    // 7.7 Punctuators

    function scanPunctuator() {
        var start = index,
            code = source.charCodeAt(index),
            code2,
            ch1 = source[index],
            ch2;

        switch (code) {

        // Check for most common single-character punctuators.
        case 46:   // . dot
        case 40:   // ( open bracket
        case 41:   // ) close bracket
        case 59:   // ; semicolon
        case 44:   // , comma
        case 123:  // { open curly brace
        case 125:  // } close curly brace
        case 91:   // [
        case 93:   // ]
        case 58:   // :
        case 63:   // ?
            ++index;
            return {
                type: Token.Punctuator,
                value: String.fromCharCode(code),
                range: [start, index]
            };

        default:
            code2 = source.charCodeAt(index + 1);

            // '=' (char #61) marks an assignment or comparison operator.
            if (code2 === 61) {
                switch (code) {
                case 37:  // %
                case 38:  // &
                case 42:  // *:
                case 43:  // +
                case 45:  // -
                case 47:  // /
                case 60:  // <
                case 62:  // >
                case 124: // |
                    index += 2;
                    return {
                        type: Token.Punctuator,
                        value: String.fromCharCode(code) + String.fromCharCode(code2),
                        range: [start, index]
                    };

                case 33: // !
                case 61: // =
                    index += 2;

                    // !== and ===
                    if (source.charCodeAt(index) === 61) {
                        ++index;
                    }
                    return {
                        type: Token.Punctuator,
                        value: source.slice(start, index),
                        range: [start, index]
                    };
                default:
                    break;
                }
            }
            break;
        }

        // Peek more characters.

        ch2 = source[index + 1];

        // Other 2-character punctuators: && ||

        if (ch1 === ch2 && ('&|'.indexOf(ch1) >= 0)) {
            index += 2;
            return {
                type: Token.Punctuator,
                value: ch1 + ch2,
                range: [start, index]
            };
        }

        if ('<>=!+-*%&|^/'.indexOf(ch1) >= 0) {
            ++index;
            return {
                type: Token.Punctuator,
                value: ch1,
                range: [start, index]
            };
        }

        throwError({}, Messages.UnexpectedToken, 'ILLEGAL');
    }

    // 7.8.3 Numeric Literals
    function scanNumericLiteral() {
        var number, start, ch;

        ch = source[index];
        assert(isDecimalDigit(ch.charCodeAt(0)) || (ch === '.'),
            'Numeric literal must start with a decimal digit or a decimal point');

        start = index;
        number = '';
        if (ch !== '.') {
            number = source[index++];
            ch = source[index];

            // Hex number starts with '0x'.
            // Octal number starts with '0'.
            if (number === '0') {
                // decimal number starts with '0' such as '09' is illegal.
                if (ch && isDecimalDigit(ch.charCodeAt(0))) {
                    throwError({}, Messages.UnexpectedToken, 'ILLEGAL');
                }
            }

            while (isDecimalDigit(source.charCodeAt(index))) {
                number += source[index++];
            }
            ch = source[index];
        }

        if (ch === '.') {
            number += source[index++];
            while (isDecimalDigit(source.charCodeAt(index))) {
                number += source[index++];
            }
            ch = source[index];
        }

        if (ch === 'e' || ch === 'E') {
            number += source[index++];

            ch = source[index];
            if (ch === '+' || ch === '-') {
                number += source[index++];
            }
            if (isDecimalDigit(source.charCodeAt(index))) {
                while (isDecimalDigit(source.charCodeAt(index))) {
                    number += source[index++];
                }
            } else {
                throwError({}, Messages.UnexpectedToken, 'ILLEGAL');
            }
        }

        if (isIdentifierStart(source.charCodeAt(index))) {
            throwError({}, Messages.UnexpectedToken, 'ILLEGAL');
        }

        return {
            type: Token.NumericLiteral,
            value: parseFloat(number),
            range: [start, index]
        };
    }

    // 7.8.4 String Literals

    function scanStringLiteral() {
        var str = '', quote, start, ch, octal = false;

        quote = source[index];
        assert((quote === '\'' || quote === '"'),
            'String literal must starts with a quote');

        start = index;
        ++index;

        while (index < length) {
            ch = source[index++];

            if (ch === quote) {
                quote = '';
                break;
            } else if (ch === '\\') {
                ch = source[index++];
                if (!ch || !isLineTerminator(ch.charCodeAt(0))) {
                    switch (ch) {
                    case 'n':
                        str += '\n';
                        break;
                    case 'r':
                        str += '\r';
                        break;
                    case 't':
                        str += '\t';
                        break;
                    case 'b':
                        str += '\b';
                        break;
                    case 'f':
                        str += '\f';
                        break;
                    case 'v':
                        str += '\x0B';
                        break;

                    default:
                        str += ch;
                        break;
                    }
                } else {
                    if (ch ===  '\r' && source[index] === '\n') {
                        ++index;
                    }
                }
            } else if (isLineTerminator(ch.charCodeAt(0))) {
                break;
            } else {
                str += ch;
            }
        }

        if (quote !== '') {
            throwError({}, Messages.UnexpectedToken, 'ILLEGAL');
        }

        return {
            type: Token.StringLiteral,
            value: str,
            octal: octal,
            range: [start, index]
        };
    }

    function isIdentifierName(token) {
        return token.type === Token.Identifier ||
            token.type === Token.Keyword ||
            token.type === Token.BooleanLiteral ||
            token.type === Token.NullLiteral;
    }

    function advance() {
        var ch;

        skipWhitespace();

        if (index >= length) {
            return {
                type: Token.EOF,
                range: [index, index]
            };
        }

        ch = source.charCodeAt(index);

        // Very common: ( and ) and ;
        if (ch === 40 || ch === 41 || ch === 58) {
            return scanPunctuator();
        }

        // String literal starts with single quote (#39) or double quote (#34).
        if (ch === 39 || ch === 34) {
            return scanStringLiteral();
        }

        if (isIdentifierStart(ch)) {
            return scanIdentifier();
        }

        // Dot (.) char #46 can also start a floating-point number, hence the need
        // to check the next character.
        if (ch === 46) {
            if (isDecimalDigit(source.charCodeAt(index + 1))) {
                return scanNumericLiteral();
            }
            return scanPunctuator();
        }

        if (isDecimalDigit(ch)) {
            return scanNumericLiteral();
        }

        return scanPunctuator();
    }

    function lex() {
        var token;

        token = lookahead;
        index = token.range[1];

        lookahead = advance();

        index = token.range[1];

        return token;
    }

    function peek() {
        var pos;

        pos = index;
        lookahead = advance();
        index = pos;
    }

    // Throw an exception

    function throwError(token, messageFormat) {
        var error,
            args = Array.prototype.slice.call(arguments, 2),
            msg = messageFormat.replace(
                /%(\d)/g,
                function (whole, index) {
                    assert(index < args.length, 'Message reference must be in range');
                    return args[index];
                }
            );

        error = new Error(msg);
        error.index = index;
        error.description = msg;
        throw error;
    }

    // Throw an exception because of the token.

    function throwUnexpected(token) {
        throwError(token, Messages.UnexpectedToken, token.value);
    }

    // Expect the next token to match the specified punctuator.
    // If not, an exception will be thrown.

    function expect(value) {
        var token = lex();
        if (token.type !== Token.Punctuator || token.value !== value) {
            throwUnexpected(token);
        }
    }

    // Return true if the next token matches the specified punctuator.

    function match(value) {
        return lookahead.type === Token.Punctuator && lookahead.value === value;
    }

    // Return true if the next token matches the specified keyword

    function matchKeyword(keyword) {
        return lookahead.type === Token.Keyword && lookahead.value === keyword;
    }

    function consumeSemicolon() {
        // Catch the very common case first: immediately a semicolon (char #59).
        if (source.charCodeAt(index) === 59) {
            lex();
            return;
        }

        skipWhitespace();

        if (match(';')) {
            lex();
            return;
        }

        if (lookahead.type !== Token.EOF && !match('}')) {
            throwUnexpected(lookahead);
        }
    }

    // 11.1.4 Array Initialiser

    function parseArrayInitialiser() {
        var elements = [];

        expect('[');

        while (!match(']')) {
            if (match(',')) {
                lex();
                elements.push(null);
            } else {
                elements.push(parseExpression());

                if (!match(']')) {
                    expect(',');
                }
            }
        }

        expect(']');

        return delegate.createArrayExpression(elements);
    }

    // 11.1.5 Object Initialiser

    function parseObjectPropertyKey() {
        var token;

        skipWhitespace();
        token = lex();

        // Note: This function is called only from parseObjectProperty(), where
        // EOF and Punctuator tokens are already filtered out.
        if (token.type === Token.StringLiteral || token.type === Token.NumericLiteral) {
            return delegate.createLiteral(token);
        }

        return delegate.createIdentifier(token.value);
    }

    function parseObjectProperty() {
        var token, key;

        token = lookahead;
        skipWhitespace();

        if (token.type === Token.EOF || token.type === Token.Punctuator) {
            throwUnexpected(token);
        }

        key = parseObjectPropertyKey();
        expect(':');
        return delegate.createProperty('init', key, parseExpression());
    }

    function parseObjectInitialiser() {
        var properties = [];

        expect('{');

        while (!match('}')) {
            properties.push(parseObjectProperty());

            if (!match('}')) {
                expect(',');
            }
        }

        expect('}');

        return delegate.createObjectExpression(properties);
    }

    // 11.1.6 The Grouping Operator

    function parseGroupExpression() {
        var expr;

        expect('(');

        expr = parseExpression();

        expect(')');

        return expr;
    }


    // 11.1 Primary Expressions

    function parsePrimaryExpression() {
        var type, token, expr;

        if (match('(')) {
            return parseGroupExpression();
        }

        type = lookahead.type;

        if (type === Token.Identifier) {
            expr = delegate.createIdentifier(lex().value);
        } else if (type === Token.StringLiteral || type === Token.NumericLiteral) {
            expr = delegate.createLiteral(lex());
        } else if (type === Token.Keyword) {
            if (matchKeyword('this')) {
                lex();
                expr = delegate.createThisExpression();
            }
        } else if (type === Token.BooleanLiteral) {
            token = lex();
            token.value = (token.value === 'true');
            expr = delegate.createLiteral(token);
        } else if (type === Token.NullLiteral) {
            token = lex();
            token.value = null;
            expr = delegate.createLiteral(token);
        } else if (match('[')) {
            expr = parseArrayInitialiser();
        } else if (match('{')) {
            expr = parseObjectInitialiser();
        }

        if (expr) {
            return expr;
        }

        throwUnexpected(lex());
    }

    // 11.2 Left-Hand-Side Expressions

    function parseArguments() {
        var args = [];

        expect('(');

        if (!match(')')) {
            while (index < length) {
                args.push(parseExpression());
                if (match(')')) {
                    break;
                }
                expect(',');
            }
        }

        expect(')');

        return args;
    }

    function parseNonComputedProperty() {
        var token;

        token = lex();

        if (!isIdentifierName(token)) {
            throwUnexpected(token);
        }

        return delegate.createIdentifier(token.value);
    }

    function parseNonComputedMember() {
        expect('.');

        return parseNonComputedProperty();
    }

    function parseComputedMember() {
        var expr;

        expect('[');

        expr = parseExpression();

        expect(']');

        return expr;
    }

    function parseLeftHandSideExpression() {
        var expr, property;

        expr = parsePrimaryExpression();

        while (match('.') || match('[')) {
            if (match('[')) {
                property = parseComputedMember();
                expr = delegate.createMemberExpression('[', expr, property);
            } else {
                property = parseNonComputedMember();
                expr = delegate.createMemberExpression('.', expr, property);
            }
        }

        return expr;
    }

    // 11.3 Postfix Expressions

    var parsePostfixExpression = parseLeftHandSideExpression;

    // 11.4 Unary Operators

    function parseUnaryExpression() {
        var token, expr;

        if (lookahead.type !== Token.Punctuator && lookahead.type !== Token.Keyword) {
            expr = parsePostfixExpression();
        } else if (match('+') || match('-') || match('!')) {
            token = lex();
            expr = parseUnaryExpression();
            expr = delegate.createUnaryExpression(token.value, expr);
        } else if (matchKeyword('delete') || matchKeyword('void') || matchKeyword('typeof')) {
            throwError({}, Messages.UnexpectedToken);
        } else {
            expr = parsePostfixExpression();
        }

        return expr;
    }

    function binaryPrecedence(token) {
        var prec = 0;

        if (token.type !== Token.Punctuator && token.type !== Token.Keyword) {
            return 0;
        }

        switch (token.value) {
        case '||':
            prec = 1;
            break;

        case '&&':
            prec = 2;
            break;

        case '==':
        case '!=':
        case '===':
        case '!==':
            prec = 6;
            break;

        case '<':
        case '>':
        case '<=':
        case '>=':
        case 'instanceof':
            prec = 7;
            break;

        case 'in':
            prec = 7;
            break;

        case '+':
        case '-':
            prec = 9;
            break;

        case '*':
        case '/':
        case '%':
            prec = 11;
            break;

        default:
            break;
        }

        return prec;
    }

    // 11.5 Multiplicative Operators
    // 11.6 Additive Operators
    // 11.7 Bitwise Shift Operators
    // 11.8 Relational Operators
    // 11.9 Equality Operators
    // 11.10 Binary Bitwise Operators
    // 11.11 Binary Logical Operators

    function parseBinaryExpression() {
        var expr, token, prec, stack, right, operator, left, i;

        left = parseUnaryExpression();

        token = lookahead;
        prec = binaryPrecedence(token);
        if (prec === 0) {
            return left;
        }
        token.prec = prec;
        lex();

        right = parseUnaryExpression();

        stack = [left, token, right];

        while ((prec = binaryPrecedence(lookahead)) > 0) {

            // Reduce: make a binary expression from the three topmost entries.
            while ((stack.length > 2) && (prec <= stack[stack.length - 2].prec)) {
                right = stack.pop();
                operator = stack.pop().value;
                left = stack.pop();
                expr = delegate.createBinaryExpression(operator, left, right);
                stack.push(expr);
            }

            // Shift.
            token = lex();
            token.prec = prec;
            stack.push(token);
            expr = parseUnaryExpression();
            stack.push(expr);
        }

        // Final reduce to clean-up the stack.
        i = stack.length - 1;
        expr = stack[i];
        while (i > 1) {
            expr = delegate.createBinaryExpression(stack[i - 1].value, stack[i - 2], expr);
            i -= 2;
        }

        return expr;
    }


    // 11.12 Conditional Operator

    function parseConditionalExpression() {
        var expr, consequent, alternate;

        expr = parseBinaryExpression();

        if (match('?')) {
            lex();
            consequent = parseConditionalExpression();
            expect(':');
            alternate = parseConditionalExpression();

            expr = delegate.createConditionalExpression(expr, consequent, alternate);
        }

        return expr;
    }

    // Simplification since we do not support AssignmentExpression.
    var parseExpression = parseConditionalExpression;

    // Polymer Syntax extensions

    // Filter ::
    //   Identifier
    //   Identifier "(" ")"
    //   Identifier "(" FilterArguments ")"

    function parseFilter() {
        var identifier, args;

        identifier = lex();

        if (identifier.type !== Token.Identifier) {
            throwUnexpected(identifier);
        }

        args = match('(') ? parseArguments() : [];

        return delegate.createFilter(identifier.value, args);
    }

    // Filters ::
    //   "|" Filter
    //   Filters "|" Filter

    function parseFilters() {
        while (match('|')) {
            lex();
            parseFilter();
        }
    }

    // TopLevel ::
    //   LabelledExpressions
    //   AsExpression
    //   InExpression
    //   FilterExpression

    // AsExpression ::
    //   FilterExpression as Identifier

    // InExpression ::
    //   Identifier, Identifier in FilterExpression
    //   Identifier in FilterExpression

    // FilterExpression ::
    //   Expression
    //   Expression Filters

    function parseTopLevel() {
        skipWhitespace();
        peek();

        var expr = parseExpression();
        if (expr) {
            if (lookahead.value === ',' || lookahead.value == 'in' &&
                       expr.type === Syntax.Identifier) {
                parseInExpression(expr);
            } else {
                parseFilters();
                if (lookahead.value === 'as') {
                    parseAsExpression(expr);
                } else {
                    delegate.createTopLevel(expr);
                }
            }
        }

        if (lookahead.type !== Token.EOF) {
            throwUnexpected(lookahead);
        }
    }

    function parseAsExpression(expr) {
        lex();  // as
        var identifier = lex().value;
        delegate.createAsExpression(expr, identifier);
    }

    function parseInExpression(identifier) {
        var indexName;
        if (lookahead.value === ',') {
            lex();
            if (lookahead.type !== Token.Identifier)
                throwUnexpected(lookahead);
            indexName = lex().value;
        }

        lex();  // in
        var expr = parseExpression();
        parseFilters();
        delegate.createInExpression(identifier.name, indexName, expr);
    }

    function parse(code, inDelegate) {
        delegate = inDelegate;
        source = code;
        index = 0;
        length = source.length;
        lookahead = null;
        state = {
            labelSet: {}
        };

        return parseTopLevel();
    }

    global.esprima = {
        parse: parse
    };
})(this);

// Copyright (c) 2014 The Polymer Project Authors. All rights reserved.
// This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
// The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
// The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
// Code distributed by Google as part of the polymer project is also
// subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt

(function (global) {
  'use strict';

  // JScript does not have __proto__. We wrap all object literals with
  // createObject which uses Object.create, Object.defineProperty and
  // Object.getOwnPropertyDescriptor to create a new object that does the exact
  // same thing. The main downside to this solution is that we have to extract
  // all those property descriptors for IE.
  var createObject = ('__proto__' in {}) ?
      function(obj) { return obj; } :
      function(obj) {
        var proto = obj.__proto__;
        if (!proto)
          return obj;
        var newObject = Object.create(proto);
        Object.getOwnPropertyNames(obj).forEach(function(name) {
          Object.defineProperty(newObject, name,
                               Object.getOwnPropertyDescriptor(obj, name));
        });
        return newObject;
      };

  function prepareBinding(expressionText, name, node, filterRegistry) {
    var expression;
    try {
      expression = getExpression(expressionText);
      if (expression.scopeIdent &&
          (node.nodeType !== Node.ELEMENT_NODE ||
           node.tagName !== 'TEMPLATE' ||
           (name !== 'bind' && name !== 'repeat'))) {
        throw Error('as and in can only be used within <template bind/repeat>');
      }
    } catch (ex) {
      console.error('Invalid expression syntax: ' + expressionText, ex);
      return;
    }

    return function(model, node, oneTime) {
      var binding = expression.getBinding(model, filterRegistry, oneTime);
      if (expression.scopeIdent && binding) {
        node.polymerExpressionScopeIdent_ = expression.scopeIdent;
        if (expression.indexIdent)
          node.polymerExpressionIndexIdent_ = expression.indexIdent;
      }

      return binding;
    }
  }

  // TODO(rafaelw): Implement simple LRU.
  var expressionParseCache = Object.create(null);

  function getExpression(expressionText) {
    var expression = expressionParseCache[expressionText];
    if (!expression) {
      var delegate = new ASTDelegate();
      esprima.parse(expressionText, delegate);
      expression = new Expression(delegate);
      expressionParseCache[expressionText] = expression;
    }
    return expression;
  }

  function Literal(value) {
    this.value = value;
    this.valueFn_ = undefined;
  }

  Literal.prototype = {
    valueFn: function() {
      if (!this.valueFn_) {
        var value = this.value;
        this.valueFn_ = function() {
          return value;
        }
      }

      return this.valueFn_;
    }
  }

  function IdentPath(name) {
    this.name = name;
    this.path = Path.get(name);
  }

  IdentPath.prototype = {
    valueFn: function() {
      if (!this.valueFn_) {
        var name = this.name;
        var path = this.path;
        this.valueFn_ = function(model, observer) {
          if (observer)
            observer.addPath(model, path);

          return path.getValueFrom(model);
        }
      }

      return this.valueFn_;
    },

    setValue: function(model, newValue) {
      if (this.path.length == 1);
        model = findScope(model, this.path[0]);

      return this.path.setValueFrom(model, newValue);
    }
  };

  function MemberExpression(object, property, accessor) {
    // convert literal computed property access where literal value is a value
    // path to ident dot-access.
    if (accessor == '[' &&
        property instanceof Literal &&
        Path.get(property.value).valid) {
      accessor = '.';
      property = new IdentPath(property.value);
    }

    this.dynamicDeps = typeof object == 'function' || object.dynamic;

    this.dynamic = typeof property == 'function' ||
                   property.dynamic ||
                   accessor == '[';

    this.simplePath =
        !this.dynamic &&
        !this.dynamicDeps &&
        property instanceof IdentPath &&
        (object instanceof MemberExpression || object instanceof IdentPath);

    this.object = this.simplePath ? object : getFn(object);
    this.property = accessor == '.' ? property : getFn(property);
  }

  MemberExpression.prototype = {
    get fullPath() {
      if (!this.fullPath_) {
        var last = this.object instanceof IdentPath ?
            this.object.name : this.object.fullPath;
        this.fullPath_ = Path.get(last + '.' + this.property.name);
      }

      return this.fullPath_;
    },

    valueFn: function() {
      if (!this.valueFn_) {
        var object = this.object;

        if (this.simplePath) {
          var path = this.fullPath;

          this.valueFn_ = function(model, observer) {
            if (observer)
              observer.addPath(model, path);

            return path.getValueFrom(model);
          };
        } else if (this.property instanceof IdentPath) {
          var path = Path.get(this.property.name);

          this.valueFn_ = function(model, observer) {
            var context = object(model, observer);

            if (observer)
              observer.addPath(context, path);

            return path.getValueFrom(context);
          }
        } else {
          // Computed property.
          var property = this.property;

          this.valueFn_ = function(model, observer) {
            var context = object(model, observer);
            var propName = property(model, observer);
            if (observer)
              observer.addPath(context, propName);

            return context ? context[propName] : undefined;
          };
        }
      }
      return this.valueFn_;
    },

    setValue: function(model, newValue) {
      if (this.simplePath) {
        this.fullPath.setValueFrom(model, newValue);
        return newValue;
      }

      var object = this.object(model);
      var propName = this.property instanceof IdentPath ? this.property.name :
          this.property(model);
      return object[propName] = newValue;
    }
  };

  function Filter(name, args) {
    this.name = name;
    this.args = [];
    for (var i = 0; i < args.length; i++) {
      this.args[i] = getFn(args[i]);
    }
  }

  Filter.prototype = {
    transform: function(value, toModelDirection, filterRegistry, model,
                        observer) {
      var fn = filterRegistry[this.name];
      var context = model;
      if (fn) {
        context = undefined;
      } else {
        fn = context[this.name];
        if (!fn) {
          console.error('Cannot find filter: ' + this.name);
          return;
        }
      }

      // If toModelDirection is falsey, then the "normal" (dom-bound) direction
      // is used. Otherwise, it looks for a 'toModel' property function on the
      // object.
      if (toModelDirection) {
        fn = fn.toModel;
      } else if (typeof fn.toDOM == 'function') {
        fn = fn.toDOM;
      }

      if (typeof fn != 'function') {
        console.error('No ' + (toModelDirection ? 'toModel' : 'toDOM') +
                      ' found on' + this.name);
        return;
      }

      var args = [value];
      for (var i = 0; i < this.args.length; i++) {
        args[i + 1] = getFn(this.args[i])(model, observer);
      }

      return fn.apply(context, args);
    }
  };

  function notImplemented() { throw Error('Not Implemented'); }

  var unaryOperators = {
    '+': function(v) { return +v; },
    '-': function(v) { return -v; },
    '!': function(v) { return !v; }
  };

  var binaryOperators = {
    '+': function(l, r) { return l+r; },
    '-': function(l, r) { return l-r; },
    '*': function(l, r) { return l*r; },
    '/': function(l, r) { return l/r; },
    '%': function(l, r) { return l%r; },
    '<': function(l, r) { return l<r; },
    '>': function(l, r) { return l>r; },
    '<=': function(l, r) { return l<=r; },
    '>=': function(l, r) { return l>=r; },
    '==': function(l, r) { return l==r; },
    '!=': function(l, r) { return l!=r; },
    '===': function(l, r) { return l===r; },
    '!==': function(l, r) { return l!==r; },
    '&&': function(l, r) { return l&&r; },
    '||': function(l, r) { return l||r; },
  };

  function getFn(arg) {
    return typeof arg == 'function' ? arg : arg.valueFn();
  }

  function ASTDelegate() {
    this.expression = null;
    this.filters = [];
    this.deps = {};
    this.currentPath = undefined;
    this.scopeIdent = undefined;
    this.indexIdent = undefined;
    this.dynamicDeps = false;
  }

  ASTDelegate.prototype = {
    createUnaryExpression: function(op, argument) {
      if (!unaryOperators[op])
        throw Error('Disallowed operator: ' + op);

      argument = getFn(argument);

      return function(model, observer) {
        return unaryOperators[op](argument(model, observer));
      };
    },

    createBinaryExpression: function(op, left, right) {
      if (!binaryOperators[op])
        throw Error('Disallowed operator: ' + op);

      left = getFn(left);
      right = getFn(right);

      return function(model, observer) {
        return binaryOperators[op](left(model, observer),
                                   right(model, observer));
      };
    },

    createConditionalExpression: function(test, consequent, alternate) {
      test = getFn(test);
      consequent = getFn(consequent);
      alternate = getFn(alternate);

      return function(model, observer) {
        return test(model, observer) ?
            consequent(model, observer) : alternate(model, observer);
      }
    },

    createIdentifier: function(name) {
      var ident = new IdentPath(name);
      ident.type = 'Identifier';
      return ident;
    },

    createMemberExpression: function(accessor, object, property) {
      var ex = new MemberExpression(object, property, accessor);
      if (ex.dynamicDeps)
        this.dynamicDeps = true;
      return ex;
    },

    createLiteral: function(token) {
      return new Literal(token.value);
    },

    createArrayExpression: function(elements) {
      for (var i = 0; i < elements.length; i++)
        elements[i] = getFn(elements[i]);

      return function(model, observer) {
        var arr = []
        for (var i = 0; i < elements.length; i++)
          arr.push(elements[i](model, observer));
        return arr;
      }
    },

    createProperty: function(kind, key, value) {
      return {
        key: key instanceof IdentPath ? key.name : key.value,
        value: value
      };
    },

    createObjectExpression: function(properties) {
      for (var i = 0; i < properties.length; i++)
        properties[i].value = getFn(properties[i].value);

      return function(model, observer) {
        var obj = {};
        for (var i = 0; i < properties.length; i++)
          obj[properties[i].key] = properties[i].value(model, observer);
        return obj;
      }
    },

    createFilter: function(name, args) {
      this.filters.push(new Filter(name, args));
    },

    createAsExpression: function(expression, scopeIdent) {
      this.expression = expression;
      this.scopeIdent = scopeIdent;
    },

    createInExpression: function(scopeIdent, indexIdent, expression) {
      this.expression = expression;
      this.scopeIdent = scopeIdent;
      this.indexIdent = indexIdent;
    },

    createTopLevel: function(expression) {
      this.expression = expression;
    },

    createThisExpression: notImplemented
  }

  function ConstantObservable(value) {
    this.value_ = value;
  }

  ConstantObservable.prototype = {
    open: function() { return this.value_; },
    discardChanges: function() { return this.value_; },
    deliver: function() {},
    close: function() {},
  }

  function Expression(delegate) {
    this.scopeIdent = delegate.scopeIdent;
    this.indexIdent = delegate.indexIdent;

    if (!delegate.expression)
      throw Error('No expression found.');

    this.expression = delegate.expression;
    getFn(this.expression); // forces enumeration of path dependencies

    this.filters = delegate.filters;
    this.dynamicDeps = delegate.dynamicDeps;
  }

  Expression.prototype = {
    getBinding: function(model, filterRegistry, oneTime) {
      if (oneTime)
        return this.getValue(model, undefined, filterRegistry);

      var observer = new CompoundObserver();
      // captures deps.
      var firstValue = this.getValue(model, observer, filterRegistry);
      var firstTime = true;
      var self = this;

      function valueFn() {
        // deps cannot have changed on first value retrieval.
        if (firstTime) {
          firstTime = false;
          return firstValue;
        }

        if (self.dynamicDeps)
          observer.startReset();

        var value = self.getValue(model,
                                  self.dynamicDeps ? observer : undefined,
                                  filterRegistry);
        if (self.dynamicDeps)
          observer.finishReset();

        return value;
      }

      function setValueFn(newValue) {
        self.setValue(model, newValue, filterRegistry);
        return newValue;
      }

      return new ObserverTransform(observer, valueFn, setValueFn, true);
    },

    getValue: function(model, observer, filterRegistry) {
      var value = getFn(this.expression)(model, observer);
      for (var i = 0; i < this.filters.length; i++) {
        value = this.filters[i].transform(value, false, filterRegistry, model,
                                          observer);
      }

      return value;
    },

    setValue: function(model, newValue, filterRegistry) {
      var count = this.filters ? this.filters.length : 0;
      while (count-- > 0) {
        newValue = this.filters[count].transform(newValue, true, filterRegistry,
                                                 model);
      }

      if (this.expression.setValue)
        return this.expression.setValue(model, newValue);
    }
  }

  /**
   * Converts a style property name to a css property name. For example:
   * "WebkitUserSelect" to "-webkit-user-select"
   */
  function convertStylePropertyName(name) {
    return String(name).replace(/[A-Z]/g, function(c) {
      return '-' + c.toLowerCase();
    });
  }

  function isEventHandler(name) {
    return name[0] === 'o' &&
           name[1] === 'n' &&
           name[2] === '-';
  }

  var mixedCaseEventTypes = {};
  [
    'webkitAnimationStart',
    'webkitAnimationEnd',
    'webkitTransitionEnd',
    'DOMFocusOut',
    'DOMFocusIn',
    'DOMMouseScroll'
  ].forEach(function(e) {
    mixedCaseEventTypes[e.toLowerCase()] = e;
  });

  var parentScopeName = '@' + Math.random().toString(36).slice(2);

  // Single ident paths must bind directly to the appropriate scope object.
  // I.e. Pushed values in two-bindings need to be assigned to the actual model
  // object.
  function findScope(model, prop) {
    while (model[parentScopeName] &&
           !Object.prototype.hasOwnProperty.call(model, prop)) {
      model = model[parentScopeName];
    }

    return model;
  }

  function resolveEventReceiver(model, path, node) {
    if (path.length == 0)
      return undefined;

    if (path.length == 1)
      return findScope(model, path[0]);

    for (var i = 0; model != null && i < path.length - 1; i++) {
      model = model[path[i]];
    }

    return model;
  }

  function prepareEventBinding(path, name, polymerExpressions) {
    var eventType = name.substring(3);
    eventType = mixedCaseEventTypes[eventType] || eventType;

    return function(model, node, oneTime) {
      var fn, receiver, handler;
      if (typeof polymerExpressions.resolveEventHandler == 'function') {
        handler = function(e) {
          fn = fn || polymerExpressions.resolveEventHandler(model, path, node);
          fn(e, e.detail, e.currentTarget);

          if (Platform && typeof Platform.flush == 'function')
            Platform.flush();
        };
      } else {
        handler = function(e) {
          fn = fn || path.getValueFrom(model);
          receiver = receiver || resolveEventReceiver(model, path, node);

          fn.apply(receiver, [e, e.detail, e.currentTarget]);

          if (Platform && typeof Platform.flush == 'function')
            Platform.flush();
        };
      }

      node.addEventListener(eventType, handler);

      if (oneTime)
        return;

      function bindingValue() {
        return '{{ ' + path + ' }}';
      }

      return {
        open: bindingValue,
        discardChanges: bindingValue,
        close: function() {
          node.removeEventListener(eventType, handler);
        }
      };
    }
  }

  function isLiteralExpression(pathString) {
    switch (pathString) {
      case '':
        return false;

      case 'false':
      case 'null':
      case 'true':
        return true;
    }

    if (!isNaN(Number(pathString)))
      return true;

    return false;
  };

  function PolymerExpressions() {}

  PolymerExpressions.prototype = {
    // "built-in" filters
    styleObject: function(value) {
      var parts = [];
      for (var key in value) {
        parts.push(convertStylePropertyName(key) + ': ' + value[key]);
      }
      return parts.join('; ');
    },

    tokenList: function(value) {
      var tokens = [];
      for (var key in value) {
        if (value[key])
          tokens.push(key);
      }
      return tokens.join(' ');
    },

    // binding delegate API
    prepareInstancePositionChanged: function(template) {
      var indexIdent = template.polymerExpressionIndexIdent_;
      if (!indexIdent)
        return;

      return function(templateInstance, index) {
        templateInstance.model[indexIdent] = index;
      };
    },

    prepareBinding: function(pathString, name, node) {
      var path = Path.get(pathString);
      if (isEventHandler(name)) {
        if (!path.valid) {
          console.error('on-* bindings must be simple path expressions');
          return;
        }

        return prepareEventBinding(path, name, this);
      }

      if (!isLiteralExpression(pathString) && path.valid) {
        if (path.length == 1) {
          return function(model, node, oneTime) {
            if (oneTime)
              return path.getValueFrom(model);

            var scope = findScope(model, path[0]);
            return new PathObserver(scope, path);
          };
        }
        return; // bail out early if pathString is simple path.
      }

      return prepareBinding(pathString, name, node, this);
    },

    prepareInstanceModel: function(template) {
      var scopeName = template.polymerExpressionScopeIdent_;
      if (!scopeName)
        return;

      var parentScope = template.templateInstance ?
          template.templateInstance.model :
          template.model;

      var indexName = template.polymerExpressionIndexIdent_;

      return function(model) {
        var scope = Object.create(parentScope);
        scope[scopeName] = model;
        scope[indexName] = undefined;
        scope[parentScopeName] = parentScope;
        return scope;
      };
    }
  };

  global.PolymerExpressions = PolymerExpressions;
  if (global.exposeGetExpression)
    global.getExpression_ = getExpression;

  global.PolymerExpressions.prepareEventBinding = prepareEventBinding;
})(this);

/*
 * Copyright 2013 The Polymer Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style
 * license that can be found in the LICENSE file.
 */
(function(scope) {

// inject style sheet
var style = document.createElement('style');
style.textContent = 'template {display: none !important;} /* injected by platform.js */';
var head = document.querySelector('head');
head.insertBefore(style, head.firstChild);

// flush (with logging)
var flushing;
function flush() {
  if (!flushing) {
    flushing = true;
    scope.endOfMicrotask(function() {
      flushing = false;
      logFlags.data && console.group('Platform.flush()');
      scope.performMicrotaskCheckpoint();
      logFlags.data && console.groupEnd();
    });
  }
};

// polling dirty checker
// flush periodically if platform does not have object observe.
if (!Observer.hasObjectObserve) {
  var FLUSH_POLL_INTERVAL = 125;
  window.addEventListener('WebComponentsReady', function() {
    flush();
    scope.flushPoll = setInterval(flush, FLUSH_POLL_INTERVAL);
  });
} else {
  // make flush a no-op when we have Object.observe
  flush = function() {};
}

if (window.CustomElements && !CustomElements.useNative) {
  var originalImportNode = Document.prototype.importNode;
  Document.prototype.importNode = function(node, deep) {
    var imported = originalImportNode.call(this, node, deep);
    CustomElements.upgradeAll(imported);
    return imported;
  }
}

// exports
scope.flush = flush;

})(window.Platform);


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