[ServiceWorker] Make Request class better conformance with the spec.

Source/modules/serviceworkers/FetchEvent.cpp

 // 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.
 
 #include "config.h"
 #include "FetchEvent.h"
 
 #include "modules/serviceworkers/Request.h"
 #include "modules/serviceworkers/ServiceWorkerGlobalScope.h"
 #include "wtf/RefPtr.h"
 
 namespace WebCore {
 
 PassRefPtrWillBeRawPtr<FetchEvent> FetchEvent::create()
 {
     return adoptRefWillBeNoop(new FetchEvent());
 }
 
 PassRefPtrWillBeRawPtr<FetchEvent> FetchEvent::create(PassRefPtr<RespondWithObserver> observer, PassRefPtr<Request> request)
 {
     return adoptRefWillBeNoop(new FetchEvent(observer, request));
 }
 
-Request* FetchEvent::request() const
+PassRefPtr<Request> FetchEvent::request() const
 {
-    return m_request.get();
+    return m_request;
 }
 
 bool FetchEvent::isReload() const
 {
     return m_isReload;
 }
 
 void FetchEvent::respondWith(ScriptState* scriptState, const ScriptValue& value)
 {
     m_observer->respondWith(scriptState, value);
@@ skipping 23 matching lines @@
 {
     ScriptWrappable::init(this);
 }
 
 void FetchEvent::trace(Visitor* visitor)
 {
     Event::trace(visitor);
 }
 
 } // namespace WebCore