Fix AudioContext constructor for Dartc.

client/dom/scripts/template_wrapping_dom.js

 // 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.
 
 // DO NOT EDIT
 // Auto-generated Dart DOM implementation.
 
 $!CODE
 
 function __dom_native_TimeoutHander_method(_this, callback, timeout, operation) {
@@ skipping 33 matching lines @@
     return wrapper;
   } catch (e) {
     throw __dom_wrap_exception(e);
   }
 }
 
 // Native methods for factory providers.
 
 function native__AudioContextFactoryProvider_create() {
   try {
-    return __dom_wrap(new AudioContext());
+    var constructor = window.AudioContext || window.webkitAudioContext;
+    return __dom_wrap(new constructor());
   } catch (e) {
     throw __dom_wrap_exception(e);
   }
 }
 
 function native__FileReaderFactoryProvider_create() {
   try {
     return __dom_wrap(new FileReader());
   } catch (e) {
     throw __dom_wrap_exception(e);
@@ skipping 260 matching lines @@
 function native__NativeDomGlobalProperties_getWindow() {
   // TODO: Should the window be obtained from an isolate?
   return __dom_wrap(window);
 }
 
 // Declared in src/GlobalProperties.dart
 function native__NativeDomGlobalProperties_getDocument() {
   // TODO: Should the window be obtained from an isolate?
   return __dom_wrap(window.document);
 }