Oilpan: move WorkerGlobalScope to oilpan's heap.

Source/core/workers/WorkerThread.h

 /*
  * Copyright (C) 2008 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 59 matching lines @@
         static unsigned workerThreadCount();
         static void releaseFastMallocFreeMemoryInAllThreads();
 
         NotificationClient* getNotificationClient() { return m_notificationClient; }
         void setNotificationClient(NotificationClient* client) { m_notificationClient = client; }
 
     protected:
         WorkerThread(WorkerLoaderProxy&, WorkerReportingProxy&, PassOwnPtr<WorkerThreadStartupData>);
 
         // Factory method for creating a new worker context for the thread.
-        virtual PassRefPtr<WorkerGlobalScope> createWorkerGlobalScope(PassOwnPtr<WorkerThreadStartupData>) = 0;
+        virtual PassRefPtrWillBeRawPtr<WorkerGlobalScope> createWorkerGlobalScope(PassOwnPtr<WorkerThreadStartupData>) = 0;
 
         // Executes the event loop for the worker thread. Derived classes can override to perform actions before/after entering the event loop.
         virtual void runEventLoop();
 
         WorkerGlobalScope* workerGlobalScope() { return m_workerGlobalScope.get(); }
 
     private:
         // Static function executed as the core routine on the new thread. Passed a pointer to a WorkerThread object.
         static void workerThreadStart(void*);
 
         void workerThread();
 
         ThreadIdentifier m_threadID;
         WorkerRunLoop m_runLoop;
         WorkerLoaderProxy& m_workerLoaderProxy;
         WorkerReportingProxy& m_workerReportingProxy;
 
-        RefPtr<WorkerGlobalScope> m_workerGlobalScope;
+        RefPtrWillBePersistent<WorkerGlobalScope> m_workerGlobalScope;
         Mutex m_threadCreationMutex;
 
         OwnPtr<WorkerThreadStartupData> m_startupData;
 
         NotificationClient* m_notificationClient;
 
         // Used to signal thread shutdown.
         OwnPtr<blink::WebWaitableEvent> m_shutdownEvent;
     };
 
 } // namespace WebCore
 
 #endif // WorkerThread_h