Promote class to a reserved word

tests/language/src/PseudoKWTest.dart

 // Copyright (c) 2011, 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.
 // Check that we can use pseudo keywords as names in function level code.
 
 
 class PseudoKWTest {
   static testMain() {
 
     // This list is taken from the 'identifier' production
     // of the Dart grammar. It lists all the pseudo-keywords
     // that are legal identifiers at the function level.
 
     var abstract = 0;
-    var class = 0;
     var extends = 0;
     var factory = 0;
     var get = 0;
     var implements = 0;
     var import = 0;
     var interface = 0;
     var library = 0;
     var native = 0;
     var negate = 0;
     var operator = 0;
     var set = 0;
     var source = 0;
     var static = 0;
     {
       void factory(set) {
         return 0;
       }
     }
 
     get: while (extends > 0) {
       break get;
     }
 
-    return static + library * class;
+    return static + library;
   }
 }
 
 
 main() {
   PseudoKWTest.testMain();
 }