Add a testOn parameter to test() and group().

lib/src/runner/browser/iframe_test.dart

 // Copyright (c) 2015, 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 unittest.runner.browser.iframe_test;
 
 import '../../backend/live_test.dart';
 import '../../backend/live_test_controller.dart';
+import '../../backend/metadata.dart';
 import '../../backend/state.dart';
 import '../../backend/suite.dart';
 import '../../backend/test.dart';
 import '../../util/multi_channel.dart';
 import '../../util/remote_exception.dart';
 
 /// A test in a running iframe.
 class IframeTest implements Test {
   final String name;
+  final Metadata metadata;
 
   /// The channel used to communicate with the test's [IframeListener].
   final MultiChannel _channel;
 
-  IframeTest(this.name, this._channel);
+  IframeTest(this.name, this.metadata, this._channel);
 
   LiveTest load(Suite suite) {
     var controller;
     controller = new LiveTestController(suite, this, () {
       controller.setState(const State(Status.running, Result.success));
 
       var testChannel = _channel.virtualChannel();
       _channel.sink.add({
         'command': 'run',
         'channel': testChannel.id
@@ skipping 10 matching lines @@
                   new Result.parse(message['result'])));
         } else {
           assert(message['type'] == 'complete');
           controller.completer.complete();
         }
       });
     });
     return controller.liveTest;
   }
 }