[DevTools] Run tests only after all UI bits are initialized.

Source/devtools/front_end/Tests.js

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 867 matching lines @@
 
 function runTests()
 {
     uiTests._populatedInterface = true;
     var name = uiTests._pendingTestName;
     delete uiTests._pendingTestName;
     if (name)
         new TestSuite().runTest(name);
 }
 
-var oldLoadCompleted = InspectorFrontendAPI.loadCompleted;
-InspectorFrontendAPI.loadCompleted = function()
-{
-    oldLoadCompleted.call(InspectorFrontendAPI);
-    runTests();
-}
+WebInspector.notifications.addEventListener(WebInspector.NotificationService.Events.InspectorUILoadedForTests, runTests);
 
 })();
 
 }