Change WokerThread to use a blink::WebThread.

Source/core/workers/DedicatedWorkerThread.cpp

 /*
  * Copyright (C) 2009 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 41 matching lines @@
 
 DedicatedWorkerThread::~DedicatedWorkerThread()
 {
 }
 
 PassRefPtrWillBeRawPtr<WorkerGlobalScope> DedicatedWorkerThread::createWorkerGlobalScope(PassOwnPtrWillBeRawPtr<WorkerThreadStartupData> startupData)
 {
     return DedicatedWorkerGlobalScope::create(this, startupData, m_timeOrigin);
 }
 
-void DedicatedWorkerThread::runEventLoop()
+void DedicatedWorkerThread::postInitialize()
 {
-    // Notify the parent object of our current active state before calling the superclass to run the event loop.
+    // Notify the parent object of our current active state before the event
+    // loop starts processing tasks.
     m_workerObjectProxy.reportPendingActivity(workerGlobalScope()->hasPendingActivity());
-    WorkerThread::runEventLoop();
 }
 
 } // namespace blink