Make unit testing of the compiler work with the new isolate helper library.

sdk/lib/html/dart2js/html_dart2js.dart

 library html;
 
 import 'dart:collection';
 import 'dart:html_common';
 import 'dart:indexed_db';
 import 'dart:isolate';
 import 'dart:json';
 import 'dart:svg' as svg;
 import 'dart:web_audio' as web_audio;
 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
@@ skipping 28 matching lines @@
     JS('void', r'window.$dart$isolate$counter = 1');
   }
   return JS('int', r'window.$dart$isolate$counter++');
 }
 
 // Fast path to invoke JS send port.
 _callPortSync(int id, message) {
   return JS('var', r'ReceivePortSync.dispatchCall(#, #)', id, message);
 }
 
-// TODO(vsm): Plumb this properly.
-spawnDomFunction(f) => spawnFunction(f);
+spawnDomFunction(f) => IsolateNatives.spawnDomFunction(f);
 // 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.
 
 
 /// @domName AbstractWorker; @docsEditable true
 class AbstractWorker extends EventTarget native "*AbstractWorker" {
 
   /// @domName EventTarget.addEventListener, EventTarget.removeEventListener, EventTarget.dispatchEvent; @docsEditable true
   AbstractWorkerEvents get on =>
@@ skipping 25845 matching lines @@
   T next() {
     if (!hasNext) {
       throw new StateError("No more elements");
     }
     return _array[_pos++];
   }
 
   final List<T> _array;
   int _pos;
 }