[Oilpan] Move WorkerScriptController to Oilpan heap on Oilpan build

Source/core/workers/WorkerGlobalScope.h

Index: Source/core/workers/WorkerGlobalScope.h
diff --git a/Source/core/workers/WorkerGlobalScope.h b/Source/core/workers/WorkerGlobalScope.h
index 916254ed9e70d9ab4f3df5e8a890705253fdf87d..4748d930c8b86c15177b39ff6bc00f60cc6bcfa4 100644
--- a/Source/core/workers/WorkerGlobalScope.h
+++ b/Source/core/workers/WorkerGlobalScope.h
@@ -167,7 +167,7 @@ private:
     EventTarget* errorEventTarget() final;
     void didUpdateSecurityOrigin() final { }
 
-    void clearScript() { m_script.clear(); }
+    void clearScript();
     void clearInspector();
 
     static void removeURLFromMemoryCacheInternal(const KURL&);
@@ -182,7 +182,7 @@ private:
 
     mutable UseCounter::CountBits m_deprecationWarningBits;
 
-    OwnPtr<WorkerScriptController> m_script;
+    OwnPtrWillBeMember<WorkerScriptController> m_script;
     WorkerThread* m_thread;
 
     RefPtrWillBeMember<WorkerInspectorController> m_workerInspectorController;