Oilpan: move WorkerGlobalScope to oilpan's heap.

Source/core/workers/SharedWorkerGlobalScope.h

Index: Source/core/workers/SharedWorkerGlobalScope.h
diff --git a/Source/core/workers/SharedWorkerGlobalScope.h b/Source/core/workers/SharedWorkerGlobalScope.h
index ada40518a1a9b2491bde7effbea2dd6ca5b20e61..fd05ba9091270105e190e4d9fbaf13c28d5cb1b5 100644
--- a/Source/core/workers/SharedWorkerGlobalScope.h
+++ b/Source/core/workers/SharedWorkerGlobalScope.h
@@ -34,6 +34,7 @@
 #include "core/frame/csp/ContentSecurityPolicy.h"
 #include "core/workers/WorkerGlobalScope.h"
 #include "core/workers/WorkerThreadStartupData.h"
+#include "heap/Handle.h"
 
 namespace WebCore {
 
@@ -43,7 +44,7 @@ namespace WebCore {
     class SharedWorkerGlobalScope FINAL : public WorkerGlobalScope {
     public:
         typedef WorkerGlobalScope Base;
-        static PassRefPtr<SharedWorkerGlobalScope> create(const String& name, SharedWorkerThread*, PassOwnPtr<WorkerThreadStartupData>);
+        static PassRefPtrWillBeRawPtr<SharedWorkerGlobalScope> create(const String& name, SharedWorkerThread*, PassOwnPtr<WorkerThreadStartupData>);
         virtual ~SharedWorkerGlobalScope();
 
         virtual bool isSharedWorkerGlobalScope() const OVERRIDE { return true; }
@@ -57,6 +58,8 @@ namespace WebCore {
 
         SharedWorkerThread* thread();
 
+        virtual void trace(Visitor*) OVERRIDE;
+
     private:
         SharedWorkerGlobalScope(const String& name, const KURL&, const String& userAgent, SharedWorkerThread*, PassOwnPtr<WorkerClients>);
         virtual void logExceptionToConsole(const String& errorMessage, const String& sourceURL, int lineNumber, int columnNumber, PassRefPtr<ScriptCallStack>) OVERRIDE;