diff --git a/pkg/front_end/lib/src/fasta/kernel/body_builder.dart b/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
index 82fcfe8..20d6978 100644
--- a/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
@@ -392,8 +392,8 @@
     }
   }
 
-  void declareVariable(Object variable, Scope scope) {
-    String name = forest.getVariableDeclarationName(variable);
+  void declareVariable(VariableDeclaration variable, Scope scope) {
+    String name = variable.name;
     Declaration existing = scope.local[name];
     if (existing != null) {
       // This reports an error for duplicated declarations in the same scope:
@@ -407,7 +407,7 @@
       return;
     }
     LocatedMessage context = scope.declare(
-        forest.getVariableDeclarationName(variable),
+        variable.name,
         new KernelVariableBuilder(
             variable, member ?? classBuilder ?? library, uri),
         uri);
@@ -438,7 +438,7 @@
   @override
   void endMetadata(Token beginToken, Token periodBeforeName, Token endToken) {
     debugEvent("Metadata");
-    Object arguments = pop();
+    Arguments arguments = pop();
     pushQualifiedReference(beginToken.next, periodBeforeName);
     if (arguments != null) {
       push(arguments);
@@ -531,7 +531,7 @@
       }
     }
     pop(); // Type.
-    List<Object> annotations = pop();
+    List<Expression> annotations = pop();
     if (annotations != null) {
       _typeInferrer.inferMetadata(this, annotations);
       Field field = fields.first.target;
@@ -679,7 +679,7 @@
 
   @override
   void finishFunction(
-      List<Object> annotations,
+      List<Expression> annotations,
       FormalParameters<Expression, Statement, Arguments> formals,
       AsyncMarker asyncModifier,
       Statement body) {
@@ -1081,8 +1081,7 @@
   @override
   void endArguments(int count, Token beginToken, Token endToken) {
     debugEvent("Arguments");
-    List<Object> arguments =
-        new List<Object>.filled(count, null, growable: true);
+    List<Object> arguments = new List<Object>(count);
     popList(count, arguments);
     int firstNamedArgumentIndex = arguments.length;
     for (int i = 0; i < arguments.length; i++) {
@@ -1730,9 +1729,8 @@
       String value = unescapeString(token.lexeme, token, this);
       push(forest.literalString(value, token));
     } else {
-      Object count = 1 + interpolationCount * 2;
-      List<Object> parts =
-          popList(count, new List<Object>.filled(count, null, growable: true));
+      int count = 1 + interpolationCount * 2;
+      List<Object> parts = popList(count, new List<Object>(count));
       Token first = parts.first;
       Token last = parts.last;
       Quote quote = analyzeQuote(first.lexeme);
@@ -2150,16 +2148,16 @@
       int count, Token leftBracket, Token constKeyword, Token rightBracket) {
     debugEvent("LiteralList");
     List<Expression> expressions = popListForValue(count);
-    Object typeArguments = pop();
+    List<DartType> typeArguments = pop();
     DartType typeArgument;
     if (typeArguments != null) {
-      if (forest.getTypeCount(typeArguments) > 1) {
+      if (typeArguments.length > 1) {
         addProblem(
             fasta.messageListLiteralTooManyTypeArguments,
             offsetForToken(leftBracket),
             lengthOfSpan(leftBracket, leftBracket.endGroup));
       } else {
-        typeArgument = forest.getTypeAt(typeArguments, 0);
+        typeArgument = typeArguments.single;
         if (library.loader.target.strongMode) {
           typeArgument =
               instantiateToBounds(typeArgument, coreTypes.objectClass);
@@ -2200,20 +2198,21 @@
   void handleLiteralMap(
       int count, Token leftBrace, Token constKeyword, Token rightBrace) {
     debugEvent("LiteralMap");
-    List<Object> entries = forest.mapEntryList(count);
+    List<MapEntry> entries =
+        new List<MapEntry>.filled(count, null, growable: true);
     popList(count, entries);
-    Object typeArguments = pop();
+    List<DartType> typeArguments = pop();
     DartType keyType;
     DartType valueType;
     if (typeArguments != null) {
-      if (forest.getTypeCount(typeArguments) != 2) {
+      if (typeArguments.length != 2) {
         addProblem(
             fasta.messageMapLiteralTypeArgumentMismatch,
             offsetForToken(leftBrace),
             lengthOfSpan(leftBrace, leftBrace.endGroup));
       } else {
-        keyType = forest.getTypeAt(typeArguments, 0);
-        valueType = forest.getTypeAt(typeArguments, 1);
+        keyType = typeArguments[0];
+        valueType = typeArguments[1];
         if (library.loader.target.strongMode) {
           keyType = instantiateToBounds(keyType, coreTypes.objectClass);
           valueType = instantiateToBounds(valueType, coreTypes.objectClass);
@@ -2305,7 +2304,7 @@
     debugEvent("beginFunctionType");
   }
 
-  void enterFunctionTypeScope(List<Object> typeVariables) {
+  void enterFunctionTypeScope(List<KernelTypeVariableBuilder> typeVariables) {
     debugEvent("enterFunctionTypeScope");
     enterLocalScope(null,
         scope.createNestedScope("function-type scope", isModifiable: true));
@@ -2520,7 +2519,7 @@
     FormalParameterKind kind = optional("{", beginToken)
         ? FormalParameterKind.optionalNamed
         : FormalParameterKind.optionalPositional;
-    Object variables =
+    List<VariableDeclaration> variables =
         new List<VariableDeclaration>.filled(count, null, growable: true);
     popList(count, variables);
     push(new OptionalFormals(kind, variables));
@@ -2634,19 +2633,18 @@
     }
     FormalParameters<Expression, Statement, Arguments> catchParameters =
         popIfNotNull(catchKeyword);
-    Object type = popIfNotNull(onKeyword);
-    Object exception;
-    Object stackTrace;
+    DartType type = popIfNotNull(onKeyword) ?? const DynamicType();
+    VariableDeclaration exception;
+    VariableDeclaration stackTrace;
     if (catchParameters != null) {
       int requiredCount = catchParameters.required.length;
       if ((requiredCount == 1 || requiredCount == 2) &&
           catchParameters.optional == null) {
         exception = catchParameters.required[0];
-        forest.setParameterType(exception, type);
+        exception.type = type;
         if (requiredCount == 2) {
           stackTrace = catchParameters.required[1];
-          forest.setParameterType(
-              stackTrace, coreTypes.stackTraceClass.rawType);
+          stackTrace.type = coreTypes.stackTraceClass.rawType;
         }
       } else {
         // TODO(ahe): We're not storing this error in the AST.
@@ -2662,12 +2660,11 @@
         var allCount = allFormals.length;
         if (allCount >= 1) {
           exception = allFormals[0];
-          forest.setParameterType(exception, type);
+          exception.type = type;
         }
         if (allCount >= 2) {
           stackTrace = allFormals[1];
-          forest.setParameterType(
-              stackTrace, coreTypes.stackTraceClass.rawType);
+          stackTrace.type = coreTypes.stackTraceClass.rawType;
         }
       }
     }
@@ -2678,7 +2675,7 @@
   @override
   void endTryStatement(int catchCount, Token tryKeyword, Token finallyKeyword) {
     Statement finallyBlock = popStatementIfNotNull(finallyKeyword);
-    Object catches = popList(
+    List<Catch> catches = popList(
         catchCount, new List<Catch>.filled(catchCount, null, growable: true));
     Statement tryBlock = popStatement();
     if (problemInTry == null) {
@@ -2976,7 +2973,7 @@
       }
     }
 
-    List<Object> types = forest.argumentsTypeArguments(arguments);
+    List<DartType> types = forest.argumentsTypeArguments(arguments);
     if (typeParameters.length != types.length) {
       if (types.length == 0) {
         // Expected `typeParameters.length` type arguments, but none given,
@@ -3308,7 +3305,7 @@
     functionNestingLevel--;
     inCatchBlock = pop();
     switchScope = pop();
-    List<Object> typeVariables = pop();
+    List<KernelTypeVariableBuilder> typeVariables = pop();
     exitLocalScope();
     push(typeVariables ?? NullValue.TypeVariables);
   }
@@ -3322,7 +3319,7 @@
   @override
   void beginNamedFunctionExpression(Token token) {
     debugEvent("beginNamedFunctionExpression");
-    List<Object> typeVariables = pop();
+    List<KernelTypeVariableBuilder> typeVariables = pop();
     // Create an additional scope in which the named function expression is
     // declared.
     enterLocalScope("named function");
@@ -3342,8 +3339,8 @@
     exitLocalScope();
     FormalParameters<Expression, Statement, Arguments> formals = pop();
     Object declaration = pop();
-    Object returnType = pop();
-    Object hasImplicitReturnType = returnType == null;
+    DartType returnType = pop();
+    bool hasImplicitReturnType = returnType == null;
     returnType ??= const DynamicType();
     exitFunction();
     List<TypeParameter> typeParameters = typeVariableBuildersToKernel(pop());
@@ -3557,20 +3554,20 @@
   void handleLabel(Token token) {
     debugEvent("Label");
     Identifier identifier = pop();
-    push(forest.label(deprecated_extractToken(identifier), token));
+    push(new Label(identifier.name, identifier.charOffset));
   }
 
   @override
   void beginLabeledStatement(Token token, int labelCount) {
     debugEvent("beginLabeledStatement");
-    List<Object> labels =
-        new List<Object>.filled(labelCount, null, growable: true);
+    List<Label> labels =
+        new List<Label>.filled(labelCount, null, growable: true);
     popList(labelCount, labels);
     enterLocalScope(null, scope.createNestedLabelScope());
     LabelTarget target =
         new LabelTarget(labels, member, functionNestingLevel, token.charOffset);
-    for (Object label in labels) {
-      scope.declareLabel(forest.getLabelName(label), target);
+    for (Label label in labels) {
+      scope.declareLabel(label.name, target);
     }
     push(target);
   }
@@ -3695,14 +3692,13 @@
   @override
   void beginSwitchCase(int labelCount, int expressionCount, Token firstToken) {
     debugEvent("beginSwitchCase");
-    Object count = labelCount + expressionCount;
-    List<Object> labelsAndExpressions =
-        popList(count, new List<Object>.filled(count, null, growable: true));
-    List<Object> labels = <Object>[];
+    int count = labelCount + expressionCount;
+    List<Object> labelsAndExpressions = popList(count, new List<Object>(count));
+    List<Label> labels = <Label>[];
     List<Expression> expressions = <Expression>[];
     if (labelsAndExpressions != null) {
       for (Object labelOrExpression in labelsAndExpressions) {
-        if (forest.isLabel(labelOrExpression)) {
+        if (labelOrExpression is Label) {
           labels.add(labelOrExpression);
         } else {
           expressions.add(labelOrExpression);
@@ -3710,15 +3706,15 @@
       }
     }
     assert(scope == switchScope);
-    for (Object label in labels) {
-      String labelName = forest.getLabelName(label);
+    for (Label label in labels) {
+      String labelName = label.name;
       if (scope.hasLocalLabel(labelName)) {
         // TODO(ahe): Should validate this is a goto target.
         if (!scope.claimLabel(labelName)) {
           addProblem(
               fasta.templateDuplicateLabelInSwitchStatement
                   .withArguments(labelName),
-              forest.getLabelOffset(label),
+              label.charOffset,
               labelName.length);
         }
       } else {
@@ -3745,7 +3741,7 @@
     // check this switch case to see if it falls through to the next case.
     Statement block = popBlock(statementCount, firstToken, null);
     exitLocalScope();
-    List<Object> labels = pop();
+    List<Label> labels = pop();
     List<Expression> expressions = pop();
     List<int> expressionOffsets = <int>[];
     for (Expression expression in expressions) {
@@ -3791,10 +3787,10 @@
     List<SwitchCase> cases =
         new List<SwitchCase>.filled(caseCount, null, growable: true);
     for (int i = caseCount - 1; i >= 0; i--) {
-      List<Object> labels = pop();
+      List<Label> labels = pop();
       SwitchCase current = cases[i] = pop();
-      for (Object label in labels) {
-        JumpTarget target = switchScope.lookupLabel(forest.getLabelName(label));
+      for (Label label in labels) {
+        JumpTarget target = switchScope.lookupLabel(label.name);
         if (target != null) {
           target.resolveGotos(forest, current);
         }
@@ -3952,7 +3948,11 @@
     // See the code that resolves them below.
     new ClassMemberParser(listener)
         .parseTypeVariablesOpt(new Token.eof(-1)..next = token);
-    enterFunctionTypeScope(listener.pop());
+    List<Object> typeVariables = listener.pop();
+    if (typeVariables != null) {
+      typeVariables = new List<KernelTypeVariableBuilder>.from(typeVariables);
+    }
+    enterFunctionTypeScope(typeVariables);
 
     // The invocation of [enterFunctionTypeScope] above has put the type
     // variables into the scope, and now the possibly unresolved types from
@@ -4058,7 +4058,7 @@
   }
 
   List<TypeParameter> typeVariableBuildersToKernel(
-      List<Object> typeVariableBuilders) {
+      List<KernelTypeVariableBuilder> typeVariableBuilders) {
     if (typeVariableBuilders == null) return null;
     List<TypeParameter> typeParameters = new List<TypeParameter>.filled(
         typeVariableBuilders.length, null,
@@ -4500,7 +4500,7 @@
   @override
   Expression wrapInDeferredCheck(
       Expression expression, KernelPrefixBuilder prefix, int charOffset) {
-    Object check = new VariableDeclaration.forValue(
+    VariableDeclaration check = new VariableDeclaration.forValue(
         forest.checkLibraryIsLoaded(prefix.dependency))
       ..fileOffset = charOffset;
     return new DeferredCheckJudgment(check, expression);
@@ -4601,24 +4601,24 @@
 
   void resolveBreaks(Forest forest, Statement target) {
     assert(isBreakTarget);
-    for (Statement user in users) {
-      forest.resolveBreak(target, user);
+    for (BreakStatement user in users) {
+      user.target = target;
     }
     users.clear();
   }
 
   void resolveContinues(Forest forest, Statement target) {
     assert(isContinueTarget);
-    for (Statement user in users) {
-      forest.resolveContinue(target, user);
+    for (BreakStatement user in users) {
+      user.target = target;
     }
     users.clear();
   }
 
-  void resolveGotos(Forest forest, Object target) {
+  void resolveGotos(Forest forest, SwitchCase target) {
     assert(isGotoTarget);
-    for (Statement user in users) {
-      forest.resolveContinueInSwitch(target, user);
+    for (ContinueSwitchStatement user in users) {
+      user.target = target;
     }
     users.clear();
   }
@@ -4628,7 +4628,7 @@
 }
 
 class LabelTarget extends Declaration implements JumpTarget {
-  final List<Object> labels;
+  final List<Label> labels;
 
   @override
   final MemberBuilder parent;
@@ -4684,7 +4684,7 @@
     continueTarget.resolveContinues(forest, target);
   }
 
-  void resolveGotos(Forest forest, Object target) {
+  void resolveGotos(Forest forest, SwitchCase target) {
     unsupported("resolveGotos", charOffset, fileUri);
   }
 
@@ -4845,3 +4845,14 @@
         asyncToken.charOffset, null);
   }
 }
+
+/// A data holder used to hold the information about a label that is pushed on
+/// the stack.
+class Label {
+  String name;
+  int charOffset;
+
+  Label(this.name, this.charOffset);
+
+  String toString() => "label($name)";
+}
diff --git a/pkg/front_end/lib/src/fasta/kernel/fangorn.dart b/pkg/front_end/lib/src/fasta/kernel/fangorn.dart
index 6e147a8..8461648 100644
--- a/pkg/front_end/lib/src/fasta/kernel/fangorn.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/fangorn.dart
@@ -11,16 +11,12 @@
         Arguments,
         AssertInitializer,
         Block,
-        BreakStatement,
         Catch,
-        ContinueSwitchStatement,
         DartType,
-        DynamicType,
         EmptyStatement,
         Expression,
         ExpressionStatement,
         InvalidExpression,
-        LabeledStatement,
         Let,
         LibraryDependency,
         MapEntry,
@@ -29,7 +25,6 @@
         NamedExpression,
         Procedure,
         Statement,
-        SwitchCase,
         ThisExpression,
         TreeNode,
         VariableDeclaration,
@@ -263,20 +258,9 @@
   }
 
   @override
-  List<MapEntry> mapEntryList(int length) {
-    return new List<MapEntryJudgment>.filled(length, null, growable: true);
-  }
-
-  @override
   int readOffset(TreeNode node) => node.fileOffset;
 
   @override
-  int getTypeCount(List typeArguments) => typeArguments.length;
-
-  @override
-  DartType getTypeAt(List typeArguments, int index) => typeArguments[index];
-
-  @override
   Expression loadLibrary(LibraryDependency dependency, Arguments arguments) {
     return new LoadLibraryJudgment(dependency, arguments);
   }
@@ -287,7 +271,7 @@
   }
 
   @override
-  Expression asExpression(Expression expression, covariant type, Token token) {
+  Expression asExpression(Expression expression, DartType type, Token token) {
     return new AsJudgment(
         expression, typeInferenceTokensSaver?.asExpressionTokens(token), type)
       ..fileOffset = offsetForToken(token);
@@ -395,8 +379,6 @@
       VariableDeclaration stackTraceParameter,
       DartType stackTraceType,
       Statement body) {
-    exceptionType ??= const DynamicType();
-    // TODO(brianwilkerson) Get the left and right parentheses and the comma.
     return new CatchJudgment(
         typeInferenceTokensSaver?.catchStatementTokens(
             onKeyword, catchKeyword, null, null, null),
@@ -490,7 +472,7 @@
 
   @override
   Expression isExpression(
-      Expression operand, isOperator, Token notOperator, covariant type) {
+      Expression operand, isOperator, Token notOperator, DartType type) {
     int offset = offsetForToken(isOperator);
     if (notOperator != null) {
       return new IsNotJudgment(
@@ -507,11 +489,6 @@
   }
 
   @override
-  Label label(Token identifier, Token colon) {
-    return new Label(identifier.lexeme, identifier.charOffset);
-  }
-
-  @override
   Statement labeledStatement(LabelTarget target, Statement statement) =>
       statement;
 
@@ -653,17 +630,6 @@
   }
 
   @override
-  String getLabelName(Label label) => label.name;
-
-  @override
-  int getLabelOffset(Label label) => label.charOffset;
-
-  @override
-  String getVariableDeclarationName(VariableDeclaration declaration) {
-    return declaration.name;
-  }
-
-  @override
   bool isBlock(Object node) => node is Block;
 
   @override
@@ -695,36 +661,12 @@
       statement is ExpressionStatement;
 
   @override
-  bool isLabel(covariant node) => node is Label;
-
-  @override
   bool isThisExpression(Object node) => node is ThisExpression;
 
   @override
   bool isVariablesDeclaration(Object node) => node is _VariablesDeclaration;
 
   @override
-  void resolveBreak(LabeledStatement target, BreakStatement user) {
-    user.target = target;
-  }
-
-  @override
-  void resolveContinue(LabeledStatement target, BreakStatement user) {
-    user.target = target;
-  }
-
-  @override
-  void resolveContinueInSwitch(
-      SwitchCase target, ContinueSwitchStatement user) {
-    user.target = target;
-  }
-
-  @override
-  void setParameterType(VariableDeclaration parameter, DartType type) {
-    parameter.type = type ?? const DynamicType();
-  }
-
-  @override
   KernelVariableUseGenerator variableUseGenerator(
       ExpressionGeneratorHelper helper,
       Token token,
@@ -947,14 +889,3 @@
     unsupported("transformChildren", fileOffset, uri);
   }
 }
-
-/// A data holder used to hold the information about a label that is pushed on
-/// the stack.
-class Label {
-  String name;
-  int charOffset;
-
-  Label(this.name, this.charOffset);
-
-  String toString() => "label($name)";
-}
diff --git a/pkg/front_end/lib/src/fasta/kernel/forest.dart b/pkg/front_end/lib/src/fasta/kernel/forest.dart
index 26da213..86f4e31 100644
--- a/pkg/front_end/lib/src/fasta/kernel/forest.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/forest.dart
@@ -4,15 +4,23 @@
 
 library fasta.forest;
 
+import 'dart:core' hide MapEntry;
+
 import 'package:kernel/ast.dart'
     show
-        Arguments, // TODO(ahe): Remove this import.
+        Arguments,
+        Catch,
         DartType,
         Expression,
+        LibraryDependency,
+        MapEntry,
         Member,
         Name,
+        NamedExpression,
         Procedure,
-        Statement;
+        Statement,
+        TreeNode,
+        VariableDeclaration;
 
 import 'body_builder.dart' show LabelTarget;
 
@@ -51,17 +59,17 @@
   const Forest();
 
   Arguments arguments(List<Expression> positional, Token location,
-      {covariant List types, covariant List named});
+      {List<DartType> types, List<NamedExpression> named});
 
   Arguments argumentsEmpty(Token location);
 
-  List argumentsNamed(Arguments arguments);
+  List<Object> argumentsNamed(Arguments arguments);
 
   List<Expression> argumentsPositional(Arguments arguments);
 
   List argumentsTypeArguments(Arguments arguments);
 
-  void argumentsSetTypeArguments(Arguments arguments, covariant List types);
+  void argumentsSetTypeArguments(Arguments arguments, List<DartType> types);
 
   Expression asLiteralString(Expression value);
 
@@ -113,11 +121,11 @@
   Expression literalMap(
       Token constKeyword,
       bool isConst,
-      covariant keyType,
-      covariant valueType,
+      DartType keyType,
+      DartType valueType,
       Object typeArguments,
       Token leftBracket,
-      covariant List entries,
+      List<MapEntry> entries,
       Token rightBracket);
 
   /// Return a representation of a null literal at the given [location].
@@ -138,7 +146,7 @@
   /// [Operator]. The [value] is the string value of the symbol.
   Expression literalSymbolSingluar(String value, Token hash, Object component);
 
-  Expression literalType(covariant type, Token location);
+  Expression literalType(DartType type, Token location);
 
   /// Return a representation of a key/value pair in a literal map. The [key] is
   /// the representation of the expression used to compute the key. The [colon]
@@ -146,26 +154,13 @@
   /// is the representation of the expression used to compute the value.
   Object mapEntry(Expression key, Token colon, Expression value);
 
-  /// Return a list that can hold [length] representations of map entries, as
-  /// returned from [mapEntry].
-  List mapEntryList(int length);
+  int readOffset(TreeNode node);
 
-  int readOffset(covariant node);
+  Expression loadLibrary(LibraryDependency dependency, Arguments arguments);
 
-  /// Given a representation of a list of [typeArguments], return the number of
-  /// type arguments in the list.
-  int getTypeCount(covariant typeArguments);
+  Expression checkLibraryIsLoaded(LibraryDependency dependency);
 
-  /// Given a representation of a list of [typeArguments], return the type
-  /// associated with the argument at the given [index].
-  DartType getTypeAt(covariant typeArguments, int index);
-
-  Expression loadLibrary(covariant dependency, Arguments arguments);
-
-  Expression checkLibraryIsLoaded(covariant dependency);
-
-  Expression asExpression(
-      Expression expression, covariant type, Token location);
+  Expression asExpression(Expression expression, DartType type, Token location);
 
   /// Return a representation of an assert that appears in a constructor's
   /// initializer list.
@@ -190,11 +185,11 @@
   /// Return a representation of a catch clause.
   Object catchClause(
       Token onKeyword,
-      covariant exceptionType,
+      DartType exceptionType,
       Token catchKeyword,
-      covariant exceptionParameter,
-      covariant stackTraceParameter,
-      covariant stackTraceType,
+      VariableDeclaration exceptionParameter,
+      VariableDeclaration stackTraceParameter,
+      DartType stackTraceType,
       Statement body);
 
   /// Return a representation of a conditional expression. The [condition] is
@@ -211,7 +206,7 @@
 
   /// Return a representation of a do statement.
   Statement doStatement(Token doKeyword, Statement body, Token whileKeyword,
-      covariant Expression condition, Token semicolon);
+      Expression condition, Token semicolon);
 
   /// Return a representation of an expression statement composed from the
   /// [expression] and [semicolon].
@@ -225,8 +220,8 @@
   Statement forStatement(
       Token forKeyword,
       Token leftParenthesis,
-      covariant variableList,
-      covariant initializers,
+      List<VariableDeclaration> variableList,
+      List<Expression> initializers,
       Token leftSeparator,
       Expression condition,
       Statement conditionStatement,
@@ -235,7 +230,7 @@
       Statement body);
 
   /// Return a representation of an `if` statement.
-  Statement ifStatement(Token ifKeyword, covariant Expression condition,
+  Statement ifStatement(Token ifKeyword, Expression condition,
       Statement thenStatement, Token elseKeyword, Statement elseStatement);
 
   /// Return a representation of an `is` expression. The [operand] is the
@@ -243,11 +238,7 @@
   /// The [notOperator] is either the `!` or `null` if the test is not negated.
   /// The [type] is a representation of the type that is the right operand.
   Expression isExpression(
-      Expression operand, Token isOperator, Token notOperator, covariant type);
-
-  /// Return a representation of the label consisting of the given [identifer]
-  /// followed by the given [colon].
-  Object label(Token identifier, Token colon);
+      Expression operand, Token isOperator, Token notOperator, DartType type);
 
   /// Return a representation of a [statement] that has one or more labels (from
   /// the [target]) associated with it.
@@ -297,11 +288,12 @@
   /// might be provided, in which case it could be returned instead of the
   /// representation of the try statement.
   Statement tryStatement(Token tryKeyword, Statement body,
-      covariant catchClauses, Token finallyKeyword, Statement finallyBlock);
+      List<Catch> catchClauses, Token finallyKeyword, Statement finallyBlock);
 
-  Statement variablesDeclaration(covariant List declarations, Uri uri);
+  Statement variablesDeclaration(
+      List<VariableDeclaration> declarations, Uri uri);
 
-  Object variablesDeclarationExtractDeclarations(
+  List<VariableDeclaration> variablesDeclarationExtractDeclarations(
       covariant Statement variablesDeclaration);
 
   Statement wrapVariables(Statement statement);
@@ -309,7 +301,7 @@
   /// Return a representation of a while statement introduced by the
   /// [whileKeyword] and consisting of the given [condition] and [body].
   Statement whileStatement(
-      Token whileKeyword, covariant Expression condition, Statement body);
+      Token whileKeyword, Expression condition, Statement body);
 
   /// Return a representation of a yield statement consisting of the
   /// [yieldKeyword], [star], [expression], and [semicolon]. The [star] is null
@@ -320,15 +312,6 @@
   /// Return the expression from the given expression [statement].
   Expression getExpressionFromExpressionStatement(Statement statement);
 
-  /// Return the name of the given [label].
-  String getLabelName(covariant label);
-
-  /// Return the offset of the given [label].
-  int getLabelOffset(covariant label);
-
-  /// Return the name of the given variable [declaration].
-  String getVariableDeclarationName(covariant declaration);
-
   bool isBlock(Object node);
 
   /// Return `true` if the given [statement] is the representation of an empty
@@ -341,31 +324,12 @@
   /// expression statement.
   bool isExpressionStatement(Statement statement);
 
-  /// Return `true` if the given [node] is a label.
-  bool isLabel(covariant node);
-
   bool isThisExpression(Object node);
 
   bool isVariablesDeclaration(Object node);
 
-  /// Record that the [user] (a break statement) is associated with the [target]
-  /// statement.
-  void resolveBreak(covariant Statement target, covariant Statement user);
-
-  /// Record that the [user] (a continue statement) is associated with the
-  /// [target] statement.
-  void resolveContinue(covariant Statement target, covariant Statement user);
-
-  /// Record that the [user] (a continue statement inside a switch case) is
-  /// associated with the [target] statement.
-  void resolveContinueInSwitch(
-      covariant Object target, covariant Statement user);
-
-  /// Set the type of the [parameter] to the given [type].
-  void setParameterType(covariant parameter, covariant type);
-
   Generator variableUseGenerator(ExpressionGeneratorHelper helper,
-      Token location, covariant variable, DartType promotedType);
+      Token location, VariableDeclaration variable, DartType promotedType);
 
   Generator propertyAccessGenerator(
       ExpressionGeneratorHelper helper,
diff --git a/pkg/front_end/lib/src/fasta/kernel/kernel_ast_api.dart b/pkg/front_end/lib/src/fasta/kernel/kernel_ast_api.dart
index 1e07bc1..5629444 100644
--- a/pkg/front_end/lib/src/fasta/kernel/kernel_ast_api.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/kernel_ast_api.dart
@@ -39,6 +39,7 @@
         LibraryPart,
         ListLiteral,
         Location,
+        MapEntry,
         Member,
         MethodInvocation,
         Name,
diff --git a/pkg/front_end/lib/src/fasta/kernel/kernel_shadow_ast.dart b/pkg/front_end/lib/src/fasta/kernel/kernel_shadow_ast.dart
index c5e1b74..ce99bf3 100644
--- a/pkg/front_end/lib/src/fasta/kernel/kernel_shadow_ast.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/kernel_shadow_ast.dart
@@ -1881,12 +1881,12 @@
   MapLiteralTokens tokens;
   DartType inferredType;
 
-  List<MapEntryJudgment> get judgments => entries;
+  List<MapEntry> get judgments => entries;
 
   final DartType _declaredKeyType;
   final DartType _declaredValueType;
 
-  MapLiteralJudgment(this.tokens, List<MapEntryJudgment> judgments,
+  MapLiteralJudgment(this.tokens, List<MapEntry> judgments,
       {DartType keyType, DartType valueType, bool isConst: false})
       : _declaredKeyType = keyType,
         _declaredValueType = valueType,
@@ -1924,9 +1924,9 @@
       inferredValueType = _declaredValueType ?? const DynamicType();
     }
     List<ExpressionJudgment> cachedKeyJudgments =
-        judgments.map((j) => j.keyJudgment).toList();
+        judgments.map((j) => (j as MapEntryJudgment).keyJudgment).toList();
     List<ExpressionJudgment> cachedValueJudgments =
-        judgments.map((j) => j.valueJudgment).toList();
+        judgments.map((j) => (j as MapEntryJudgment).valueJudgment).toList();
     if (inferenceNeeded || typeChecksNeeded) {
       for (MapEntryJudgment judgment in judgments) {
         judgment.infer(inferrer, inferredKeyType, inferredValueType);
diff --git a/pkg/front_end/lib/src/fasta/source/stack_listener.dart b/pkg/front_end/lib/src/fasta/source/stack_listener.dart
index bc7beda..cd41814 100644
--- a/pkg/front_end/lib/src/fasta/source/stack_listener.dart
+++ b/pkg/front_end/lib/src/fasta/source/stack_listener.dart
@@ -76,7 +76,7 @@
 
   // TODO(ahe): This doesn't belong here. Only implemented by body_builder.dart
   // and ast_builder.dart.
-  void finishFunction(List annotations, covariant formals,
+  void finishFunction(covariant List<Object> annotations, covariant formals,
       AsyncMarker asyncModifier, covariant body) {
     return unsupported("finishFunction", -1, uri);
   }