Restore invariant that stack is empty in parseFunctionBody.

pkg/analyzer/lib/src/fasta/ast_builder.dart

 // Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
 // 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 fasta.analyzer.ast_builder;
 
 import 'package:analyzer/analyzer.dart';
 import 'package:analyzer/dart/ast/ast_factory.dart' show AstFactory;
 import 'package:analyzer/dart/ast/standard_ast_factory.dart' as standard;
 import 'package:analyzer/dart/ast/token.dart' as analyzer show Token;
@@ skipping 40 matching lines @@
    * `native` support.
    */
   Parser parser;
 
   bool parseGenericMethodComments = false;
 
   /// The name of the class currently being parsed, or `null` if no class is
   /// being parsed.
   String className;
 
+  /// If true, this is building a full AST. Otherwise, only create method
+  /// bodies.
+  final bool isFullAst;
+
   AstBuilder(this.errorReporter, this.library, this.member, this.elementStore,
-      Scope scope,
+      Scope scope, this.isFullAst,
       [Uri uri])
       : uri = uri ?? library.fileUri,
         super(scope);
 
   createJumpTarget(JumpTargetKind kind, int charOffset) {
     // TODO(ahe): Implement jump targets.
     return null;
   }
 
   void beginLiteralString(Token token) {
@@ skipping 323 matching lines @@
     Statement elsePart = popIfNotNull(elseToken);
     Statement thenPart = pop();
     Expression condition = pop();
     analyzer.BeginToken leftParenthesis = ifToken.next;
     push(ast.ifStatement(ifToken, ifToken.next, condition,
         leftParenthesis.endGroup, thenPart, elseToken, elsePart));
   }
 
   void handleNoInitializers() {
     debugEvent("NoInitializers");
+    if (!isFullAst) return;
     push(NullValue.ConstructorInitializerSeparator);
     push(NullValue.ConstructorInitializers);
   }
 
   void endInitializers(int count, Token beginToken, Token endToken) {
     debugEvent("Initializers");
     List<Object> initializerObjects = popList(count) ?? const [];
+    if (!isFullAst) return;
 
     push(beginToken);
 
     var initializers = <ConstructorInitializer>[];
     for (Object initializerObject in initializerObjects) {
       if (initializerObject is FunctionExpressionInvocation) {
         Expression function = initializerObject.function;
         if (function is SuperExpression) {
           initializers.add(ast.superConstructorInvocation(function.superKeyword,
               null, null, initializerObject.argumentList));
@@ skipping 1592 matching lines @@
       } else if (identical('var', s)) {
         finalConstOrVarKeyword = token;
       } else if (identical('covariant', s)) {
         covariantKeyword = token;
       } else {
         internalError('Unhandled modifier: $s');
       }
     }
   }
 }