Revert "Add [WillBeGarbageCollected] to Event.idl"

Source/modules/serviceworkers/FetchEvent.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef FetchEvent_h
 #define FetchEvent_h
 
 #include "core/events/Event.h"
 #include "modules/serviceworkers/RespondWithObserver.h"
 
 namespace WebCore {
 
 class ExecutionContext;
 class RespondWithObserver;
 
 // A fetch event is dispatched by the client to a service worker's script
 // context. RespondWithObserver can be used to notify the client about the
 // service worker's response.
 class FetchEvent FINAL : public Event {
 public:
-    static PassRefPtrWillBeRawPtr<FetchEvent> create();
-    static PassRefPtrWillBeRawPtr<FetchEvent> create(PassRefPtr<RespondWithObserver>);
+    static PassRefPtr<FetchEvent> create();
+    static PassRefPtr<FetchEvent> create(PassRefPtr<RespondWithObserver>);
     virtual ~FetchEvent() { }
 
     void respondWith(const ScriptValue&);
 
     virtual const AtomicString& interfaceName() const OVERRIDE;
 
-    virtual void trace(Visitor*) OVERRIDE;
-
 protected:
     FetchEvent();
     explicit FetchEvent(PassRefPtr<RespondWithObserver>);
 
 private:
     RefPtr<RespondWithObserver> m_observer;
 };
 
 } // namespace WebCore
 
 #endif // FetchEvent_h