Actually start ServiceWorkerThread in EmbeddedWorker

public/web/WebServiceWorkerContextProxy.h

 /*
  * Copyright (C) 2013 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 15 matching lines @@
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef WebServiceWorkerContextProxy_h
 #define WebServiceWorkerContextProxy_h
 
 namespace blink {
 
+class WebString;
+
 // A proxy interface to talk to the worker's GlobalScope implementation.
 // All methods of this class must be called on the worker thread.
 class WebServiceWorkerContextProxy {
 public:
     virtual ~WebServiceWorkerContextProxy() { }
 
     // FIXME: Add service-worker specific methods.
 
     virtual void resumeWorkerContext() { }
     virtual void attachDevTools() { }
     virtual void reattachDevTools(const WebString& savedState) { }
     virtual void detachDevTools() { }
     virtual void dispatchDevToolsMessage(const WebString&) { }
 };
 
 } // namespace blink
 
 #endif // WebServiceWorkerContextProxy_h