Adding in-browser correctness testing via selenium.

frog/var_member.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.
 
 /** A dynamic member stub. */
 class VarMember {
   final String name;
 
   VarMember(this.name);
 
@@ skipping 229 matching lines @@
    *   'Object': function($0, capture) {
    *     return this.noSuchMethod('addEventListener', [$0],
    *       {'capture': capture});
    *   }
    * });
    */
   void generate(CodeWriter code) {
     if (_fallbackStubs.length == 0) return;
 
     code.enterBlock('\$varMethod("$name", {');
+    var lastOne = _fallbackStubs[_fallbackStubs.length - 1];
     for (var stub in _fallbackStubs) {
       code.write('"${stub.typeName}": ');
       stub.generateBody(code);
-      code.writeln(',');
+      code.writeln(stub == lastOne ? '' : ',');
     }
     code.exitBlock('});');
   }
 }
 
 String _getCallStubName(String name, Arguments args) {
   final nameBuilder = new StringBuffer('${name}\$${args.bareCount}');
   for (int i = args.bareCount; i < args.length; i++) {
     nameBuilder.add('\$').add(args.getName(i));
   }
   return nameBuilder.toString();
 }