Add terminateServiceWorker method for layout tests - blink side

Source/modules/serviceworkers/ServiceWorker.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 51 matching lines @@
     const AtomicString& state() const;
     DEFINE_ATTRIBUTE_EVENT_LISTENER(statechange);
 
     // WebServiceWorkerProxy overrides.
     virtual bool isReady() override;
     virtual void dispatchStateChangeEvent() override;
 
     // AbstractWorker overrides.
     virtual const AtomicString& interfaceName() const override;
 
+    void internalsTerminate();
 private:
     class ThenFunction;
 
     enum ProxyState {
         Initial,
         RegisterPromisePending,
         Ready,
         ContextStopped
     };
 
     static PassRefPtrWillBeRawPtr<ServiceWorker> getOrCreate(ExecutionContext*, WebType*);
     ServiceWorker(ExecutionContext*, PassOwnPtr<WebServiceWorker>);
     void setProxyState(ProxyState);
     void onPromiseResolved();
     void waitOnPromise(ScriptPromiseResolver*);
 
     // ActiveDOMObject overrides.
     virtual bool hasPendingActivity() const override;
     virtual void stop() override;
 
     OwnPtr<WebServiceWorker> m_outerWorker;
     ProxyState m_proxyState;
 };
 
 } // namespace blink
 
 #endif // ServiceWorker_h