Cache Storage: Add Platform API to retrieve CacheStorage for origin

Source/web/ServiceWorkerGlobalScopeClientImpl.cpp

 /*
  * 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 55 matching lines @@
 void ServiceWorkerGlobalScopeClientImpl::clearCachedMetadata(const WebURL& url)
 {
     m_client.clearCachedMetadata(url);
 }
 
 WebURL ServiceWorkerGlobalScopeClientImpl::scope() const
 {
     return m_client.scope();
 }
 
-WebServiceWorkerCacheStorage* ServiceWorkerGlobalScopeClientImpl::cacheStorage() const
-{
-    return m_client.cacheStorage();
-}
-
 void ServiceWorkerGlobalScopeClientImpl::didHandleActivateEvent(int eventID, WebServiceWorkerEventResult result)
 {
     m_client.didHandleActivateEvent(eventID, result);
 }
 
 void ServiceWorkerGlobalScopeClientImpl::didHandleFetchEvent(int fetchEventID)
 {
     m_client.didHandleFetchEvent(fetchEventID);
 }
 
@@ skipping 51 matching lines @@
 {
     m_client.focus(clientUUID, callback);
 }
 
 ServiceWorkerGlobalScopeClientImpl::ServiceWorkerGlobalScopeClientImpl(WebServiceWorkerContextClient& client)
     : m_client(client)
 {
 }
 
 } // namespace blink