Update AbstractWorker, Worker and SharedWorker to match the spec

Source/core/workers/Worker.h

 /*
  * Copyright (C) 2008, 2010 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 29 matching lines @@
 #include <wtf/text/AtomicStringHash.h>
 
 namespace WebCore {
 
     class ScriptExecutionContext;
     class WorkerContextProxy;
     class WorkerScriptLoader;
 
     typedef int ExceptionCode;
 
-    class Worker : public AbstractWorker, private WorkerScriptLoaderClient {
+    class Worker : public AbstractWorker, public ScriptWrappable, public ActiveDOMObject, private WorkerScriptLoaderClient {
     public:
         static PassRefPtr<Worker> create(ScriptExecutionContext*, const String& url, ExceptionCode&);
         virtual ~Worker();
 
         virtual const AtomicString& interfaceName() const OVERRIDE;
 
         void postMessage(PassRefPtr<SerializedScriptValue> message, const MessagePortArray*, ExceptionCode&);
 
         void terminate();
 
         virtual bool canSuspend() const OVERRIDE;
         virtual void stop() OVERRIDE;
         virtual bool hasPendingActivity() const OVERRIDE;
+        virtual void contextDestroyed() OVERRIDE;
+        virtual ScriptExecutionContext* scriptExecutionContext() const OVERRIDE { return ActiveDOMObject::scriptExecutionContext(); }
     
         DEFINE_ATTRIBUTE_EVENT_LISTENER(message);
 
     private:
         explicit Worker(ScriptExecutionContext*);
 
         // WorkerScriptLoaderClient callbacks
         virtual void didReceiveResponse(unsigned long identifier, const ResourceResponse&) OVERRIDE;
         virtual void notifyFinished() OVERRIDE;
 
         virtual void refEventTarget() OVERRIDE { ref(); }
         virtual void derefEventTarget() OVERRIDE { deref(); }
 
         RefPtr<WorkerScriptLoader> m_scriptLoader;
         WorkerContextProxy* m_contextProxy; // The proxy outlives the worker to perform thread shutdown.
     };
 
 } // namespace WebCore
 
 #endif // Worker_h