Dispatch the ServiceWorker "activate" event during activation

Source/modules/serviceworkers/ServiceWorkerGlobalScopeClient.h

 /*
  * Copyright (C) 2014 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 29 matching lines @@
 
 class ExecutionContext;
 class Response;
 class WorkerClients;
 
 class ServiceWorkerGlobalScopeClient : public Supplement<WorkerClients> {
     WTF_MAKE_NONCOPYABLE(ServiceWorkerGlobalScopeClient);
 public:
     virtual ~ServiceWorkerGlobalScopeClient() { }
 
+    virtual void didHandleActivateEvent(int eventID, blink::WebServiceWorkerEventResult) = 0;
     virtual void didHandleInstallEvent(int installEventID, blink::WebServiceWorkerEventResult) = 0;
     // A null response means no valid response was provided by the service worker, so fallback to native.
     virtual void didHandleFetchEvent(int fetchEventID, PassRefPtr<Response> = nullptr) = 0;
     virtual void didHandleSyncEvent(int syncEventID) = 0;
 
     static const char* supplementName();
     static ServiceWorkerGlobalScopeClient* from(ExecutionContext*);
 
 protected:
     ServiceWorkerGlobalScopeClient() { }
 };
 
 void provideServiceWorkerGlobalScopeClientToWorker(WorkerClients*, PassOwnPtr<ServiceWorkerGlobalScopeClient>);
 
 } // namespace WebCore
 
 #endif // ServiceWorkerGlobalScopeClient_h