Oilpan: move WorkerGlobalScope to oilpan's heap.

Source/core/workers/SharedWorkerThread.h

 /*
  * 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 25 matching lines @@
 namespace WebCore {
 
 struct WorkerThreadStartupData;
 
 class SharedWorkerThread : public WorkerThread {
 public:
     static PassRefPtr<SharedWorkerThread> create(const String& name, WorkerLoaderProxy&, WorkerReportingProxy&, PassOwnPtr<WorkerThreadStartupData>);
     virtual ~SharedWorkerThread();
 
 protected:
-    virtual PassRefPtr<WorkerGlobalScope> createWorkerGlobalScope(PassOwnPtr<WorkerThreadStartupData>) OVERRIDE;
+    virtual PassRefPtrWillBeRawPtr<WorkerGlobalScope> createWorkerGlobalScope(PassOwnPtr<WorkerThreadStartupData>) OVERRIDE;
 
 private:
     SharedWorkerThread(const String& name, WorkerLoaderProxy&, WorkerReportingProxy&, PassOwnPtr<WorkerThreadStartupData>);
 
     String m_name;
 };
 
 } // namespace WebCore
 
 #endif // SharedWorkerThread_h