Handle const loop variable.

pkg/compiler/lib/src/parser/parser.dart

 // Copyright (c) 2012, 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 dart2js.parser;
 
 import '../common.dart';
 import '../tokens/keyword.dart' show
     Keyword;
 import '../tokens/precedence.dart' show
@@ skipping 642 matching lines @@
 
   /**
    * Returns true if the stringValue of the [token] is [value].
    */
   bool optional(String value, Token token) {
     return identical(value, token.stringValue);
   }
 
   /**
    * Returns true if the stringValue of the [token] is either [value1],
+   * [value2], or [value3].
+   */
+  bool isOneOf3(Token token, String value1, String value2, String value3) {
+    String stringValue = token.stringValue;
+    return
+        value1 == stringValue ||
+        value2 == stringValue ||
+        value3 == stringValue;
+  }
+
+  /**
+   * Returns true if the stringValue of the [token] is either [value1],
    * [value2], [value3], or [value4].
    */
   bool isOneOf4(Token token,
                 String value1, String value2, String value3, String value4) {
     String stringValue = token.stringValue;
-    return identical(value1, stringValue) ||
-           identical(value2, stringValue) ||
-           identical(value3, stringValue) ||
-           identical(value4, stringValue);
+    return value1 == stringValue ||
+           value2 == stringValue ||
+           value3 == stringValue ||
+           value4 == stringValue;
   }
 
   bool notEofOrValue(String value, Token token) {
     return !identical(token.kind, EOF_TOKEN) &&
            !identical(value, token.stringValue);
   }
 
   Token parseType(Token token) {
     Token begin = token;
     if (isValidTypeReference(token)) {
@@ skipping 1738 matching lines @@
       }
       return parseForRest(forToken, token);
     }
   }
 
   Token parseVariablesDeclarationOrExpressionOpt(Token token) {
     final String value = token.stringValue;
     if (identical(value, ';')) {
       listener.handleNoExpression(token);
       return token;
-    } else if ((identical(value, 'var')) || (identical(value, 'final'))) {
+    } else if (isOneOf3(token, 'var', 'final', 'const')) {
       return parseVariablesDeclarationNoSemicolon(token);
     }
     Token identifier = peekIdentifierAfterType(token);
     if (identifier != null) {
       assert(identifier.isIdentifier());
       if (isOneOf4(identifier.next, '=', ';', ',', 'in')) {
         return parseVariablesDeclarationNoSemicolon(token);
       }
     }
     return parseExpression(token);
@@ skipping 283 matching lines @@
     }
     listener.handleContinueStatement(hasTarget, continueKeyword, token);
     return expectSemicolon(token);
   }
 
   Token parseEmptyStatement(Token token) {
     listener.handleEmptyStatement(token);
     return expectSemicolon(token);
   }
 }