Get rid of all the library tags.

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1584563003 .
diff --git a/lib/matcher.dart b/lib/matcher.dart
index c719fb1..f4ebf08 100644
--- a/lib/matcher.dart
+++ b/lib/matcher.dart
@@ -3,8 +3,6 @@
 // BSD-style license that can be found in the LICENSE file.
 
 /// Support for specifying test expectations, such as for unit tests.
-library matcher;
-
 export 'src/core_matchers.dart';
 export 'src/description.dart';
 export 'src/error_matchers.dart';
diff --git a/lib/mirror_matchers.dart b/lib/mirror_matchers.dart
index d244831..0ce90da 100644
--- a/lib/mirror_matchers.dart
+++ b/lib/mirror_matchers.dart
@@ -4,8 +4,6 @@
 
 /// The mirror matchers library provides some additional matchers that
 /// make use of `dart:mirrors`.
-library matcher.mirror_matchers;
-
 import 'dart:mirrors';
 
 import 'matcher.dart';
diff --git a/lib/src/core_matchers.dart b/lib/src/core_matchers.dart
index 1b001f9..a313d31 100644
--- a/lib/src/core_matchers.dart
+++ b/lib/src/core_matchers.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library matcher.core_matchers;
-
 import 'description.dart';
 import 'interfaces.dart';
 import 'util.dart';
diff --git a/lib/src/description.dart b/lib/src/description.dart
index 1da5a3a..17c5ad4 100644
--- a/lib/src/description.dart
+++ b/lib/src/description.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library matcher.description;
-
 import 'interfaces.dart';
 import 'pretty_print.dart';
 
diff --git a/lib/src/error_matchers.dart b/lib/src/error_matchers.dart
index 821e731..1f37538 100644
--- a/lib/src/error_matchers.dart
+++ b/lib/src/error_matchers.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library matcher.error_matchers;
-
 import 'core_matchers.dart';
 import 'interfaces.dart';
 
diff --git a/lib/src/interfaces.dart b/lib/src/interfaces.dart
index 984d862..0183671 100644
--- a/lib/src/interfaces.dart
+++ b/lib/src/interfaces.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library matcher.interfaces;
-
 // To decouple the reporting of errors, and allow for extensibility of
 // matchers, we make use of some interfaces.
 
diff --git a/lib/src/iterable_matchers.dart b/lib/src/iterable_matchers.dart
index 7185e92..55724b7 100644
--- a/lib/src/iterable_matchers.dart
+++ b/lib/src/iterable_matchers.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library matcher.iterable_matchers;
-
 import 'core_matchers.dart';
 import 'description.dart';
 import 'interfaces.dart';
diff --git a/lib/src/map_matchers.dart b/lib/src/map_matchers.dart
index 8facbf5..a44148f 100644
--- a/lib/src/map_matchers.dart
+++ b/lib/src/map_matchers.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library matcher.map_matchers;
-
 import 'interfaces.dart';
 import 'util.dart';
 
diff --git a/lib/src/numeric_matchers.dart b/lib/src/numeric_matchers.dart
index 770999d..0cdb98c 100644
--- a/lib/src/numeric_matchers.dart
+++ b/lib/src/numeric_matchers.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library matcher.numeric_matchers;
-
 import 'interfaces.dart';
 
 /// Returns a matcher which matches if the match argument is greater
diff --git a/lib/src/operator_matchers.dart b/lib/src/operator_matchers.dart
index 6824c5b..87ff329 100644
--- a/lib/src/operator_matchers.dart
+++ b/lib/src/operator_matchers.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library matcher.operator_matchers;
-
 import 'interfaces.dart';
 import 'util.dart';
 
diff --git a/lib/src/pretty_print.dart b/lib/src/pretty_print.dart
index c20102b..9b0a789 100644
--- a/lib/src/pretty_print.dart
+++ b/lib/src/pretty_print.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library matcher.pretty_print;
-
 import 'description.dart';
 import 'interfaces.dart';
 import 'util.dart';
diff --git a/lib/src/string_matchers.dart b/lib/src/string_matchers.dart
index 4643434..eb0b464 100644
--- a/lib/src/string_matchers.dart
+++ b/lib/src/string_matchers.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library matcher.string_matchers;
-
 import 'interfaces.dart';
 
 /// Returns a matcher which matches if the match argument is a string and
diff --git a/lib/src/util.dart b/lib/src/util.dart
index 8706009..c773402 100644
--- a/lib/src/util.dart
+++ b/lib/src/util.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library matcher.util;
-
 import 'core_matchers.dart';
 import 'interfaces.dart';
 
diff --git a/test/core_matchers_test.dart b/test/core_matchers_test.dart
index a7b30da..4d0e4bf 100644
--- a/test/core_matchers_test.dart
+++ b/test/core_matchers_test.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library matcher.core_matchers_test;
-
 import 'package:matcher/matcher.dart';
 import 'package:test/test.dart' show test, group;
 
diff --git a/test/escape_test.dart b/test/escape_test.dart
index 35a18bc..265e24a 100644
--- a/test/escape_test.dart
+++ b/test/escape_test.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library matcher.escape_test;
-
 import 'package:matcher/src/util.dart';
 import 'package:test/test.dart';
 
diff --git a/test/iterable_matchers_test.dart b/test/iterable_matchers_test.dart
index 54bc2c9..4d302c2 100644
--- a/test/iterable_matchers_test.dart
+++ b/test/iterable_matchers_test.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library matcher.iterable_matchers_test;
-
 import 'package:matcher/matcher.dart';
 import 'package:test/test.dart' show test, group;
 
diff --git a/test/mirror_matchers_test.dart b/test/mirror_matchers_test.dart
index f1781c1..5aa6a75 100644
--- a/test/mirror_matchers_test.dart
+++ b/test/mirror_matchers_test.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library matcher.mirror_test;
-
 import 'package:matcher/mirror_matchers.dart';
 import 'package:test/test.dart' show test;
 
diff --git a/test/numeric_matchers_test.dart b/test/numeric_matchers_test.dart
index d62bad6..922f303 100644
--- a/test/numeric_matchers_test.dart
+++ b/test/numeric_matchers_test.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library matcher.numeric_matchers_test;
-
 import 'package:matcher/matcher.dart';
 import 'package:test/test.dart' show test, group;
 
diff --git a/test/operator_matchers_test.dart b/test/operator_matchers_test.dart
index 003eb34..9fe77fb 100644
--- a/test/operator_matchers_test.dart
+++ b/test/operator_matchers_test.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library matcher.operator_matchers_test;
-
 import 'package:matcher/matcher.dart';
 import 'package:test/test.dart'
     show test, group, expect, throwsArgumentError;
diff --git a/test/pretty_print_test.dart b/test/pretty_print_test.dart
index ea20be9..c71a94f 100644
--- a/test/pretty_print_test.dart
+++ b/test/pretty_print_test.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library matcher.pretty_print_test;
-
 import 'dart:collection';
 
 import 'package:matcher/matcher.dart';
diff --git a/test/string_matchers_test.dart b/test/string_matchers_test.dart
index 38fa129..9a61cb0 100644
--- a/test/string_matchers_test.dart
+++ b/test/string_matchers_test.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library matcher.string_matchers_test;
-
 import 'package:matcher/matcher.dart';
 import 'package:test/test.dart' show test, group, expect;
 
diff --git a/test/test_utils.dart b/test/test_utils.dart
index f95c2b9..ffcb623 100644
--- a/test/test_utils.dart
+++ b/test/test_utils.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library matcher.test_utils;
-
 import 'dart:collection';
 
 import 'package:test/test.dart';