Fix for parsing 'const X()' with Fasta.

pkg/front_end/lib/src/fasta/analyzer/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 59 matching lines @@
       Token start, Token periodBeforeName, Token endToken) {
     debugEvent("ConstructorReference");
     SimpleIdentifier constructorName = pop();
     TypeArgumentList typeArguments = pop();
     Identifier typeNameIdentifier = pop();
     push(ast.constructorName(ast.typeName(typeNameIdentifier, typeArguments),
         toAnalyzerToken(periodBeforeName), constructorName));
   }
 
   @override
-  void handleNewExpression(Token token) {
-    debugEvent("NewExpression");
+  void handleConstExpression(Token token) {
+    debugEvent("ConstExpression");
+    _handleInstanceCreation(token);
+  }
+
+  void _handleInstanceCreation(Token token) {
     MethodInvocation arguments = pop();
     ConstructorName constructorName = pop();
     push(ast.instanceCreationExpression(
         toAnalyzerToken(token), constructorName, arguments.argumentList));
   }
 
   @override
+  void handleNewExpression(Token token) {
+    debugEvent("NewExpression");
+    _handleInstanceCreation(token);
+  }
+
+  @override
   void handleParenthesizedExpression(BeginGroupToken token) {
     debugEvent("ParenthesizedExpression");
     Expression expression = pop();
     push(ast.parenthesizedExpression(
         toAnalyzerToken(token), expression, toAnalyzerToken(token.endGroup)));
   }
 
   void handleStringPart(Token token) {
     debugEvent("StringPart");
     push(token);
@@ skipping 1357 matching lines @@
       } else if (identical('static', s)) {
         staticKeyword = token;
       } else if (identical('var', s)) {
         finalConstOrVarKeyword = token;
       } else {
         internalError('Unhandled modifier: $s');
       }
     }
   }
 }