Fix test wrapping issues.

dart/tests/lib/mirrors/native_class_test.dart

 // Copyright (c) 2013, 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 test.native_class_test;
 
 import 'dart:html';
 
 @MirrorsUsed(targets: 'dart.dom.html.Element')
 import 'dart:mirrors';
 
 import 'stringify.dart';
 
 main() {
   expect('s(dart.dom.html.Element)', reflectClass(Element).qualifiedName);
   expect(
       's(dart.dom.html.Node)', reflectClass(Element).superclass.qualifiedName);
+  window.postMessage('unittest-suite-success', '*');
 }