Support performance.now() in workers.

Source/core/workers/WorkerContext.h

 /*
  * Copyright (C) 2008, 2009 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 117 matching lines @@
         private:
             WorkerContext* m_context;
         };
         friend class Observer;
         void registerObserver(Observer*);
         void unregisterObserver(Observer*);
         void notifyObserversOfStop();
 
         virtual const SecurityOrigin* topOrigin() const OVERRIDE { return m_topOrigin.get(); }
 
+        double timeOrigin() const { return m_timeOrigin; }
+
     protected:
-        WorkerContext(const KURL&, const String& userAgent, PassOwnPtr<GroupSettings>, WorkerThread*, PassRefPtr<SecurityOrigin> topOrigin);
+        WorkerContext(const KURL&, const String& userAgent, PassOwnPtr<GroupSettings>, WorkerThread*, PassRefPtr<SecurityOrigin> topOrigin, double timeOrigin);
         void applyContentSecurityPolicyFromString(const String& contentSecurityPolicy, ContentSecurityPolicy::HeaderType);
 
         virtual void logExceptionToConsole(const String& errorMessage, const String& sourceURL, int lineNumber, PassRefPtr<ScriptCallStack>) OVERRIDE;
         void addMessageToWorkerConsole(MessageSource, MessageLevel, const String& message, const String& sourceURL, unsigned lineNumber, PassRefPtr<ScriptCallStack>, ScriptState* = 0, unsigned long requestIdentifier = 0);
 
     private:
         virtual void refScriptExecutionContext() OVERRIDE { ref(); }
         virtual void derefScriptExecutionContext() OVERRIDE { deref(); }
 
         virtual void refEventTarget() OVERRIDE { ref(); }
@@ skipping 22 matching lines @@
         mutable RefPtr<DOMURL> m_domURL;
         OwnPtr<WorkerInspectorController> m_workerInspectorController;
         bool m_closing;
         EventTargetData m_eventTargetData;
 
         HashSet<Observer*> m_workerObservers;
 
         OwnPtr<WorkerEventQueue> m_eventQueue;
 
         RefPtr<SecurityOrigin> m_topOrigin;
+
+        double m_timeOrigin;
     };
 
 } // namespace WebCore
 
 #endif // WorkerContext_h