Don't use m_fallbackRequestForServiceWorker in ResourceLoader.

Source/core/fetch/ResourceLoader.h

 /*
  * Copyright (C) 2005, 2006, 2011 Apple 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:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 94 matching lines @@
     OwnPtr<WebURLLoader> m_loader;
     Member<ResourceFetcher> m_fetcher;
 
     ResourceRequest m_request;
     ResourceRequest m_originalRequest; // Before redirects.
 
     bool m_notifiedLoadComplete;
 
     bool m_defersLoading;
     bool m_loadingMultipartContent;
-    OwnPtr<ResourceRequest> m_fallbackRequestForServiceWorker;
     ResourceRequest m_deferredRequest;
     ResourceLoaderOptions m_options;
 
     enum ResourceLoaderState {
         Initialized,
         Finishing,
         Terminated
     };
 
     enum ConnectionState {
@@ skipping 10 matching lines @@
     ResourceLoaderState m_state;
 
     // Used for sanity checking to make sure we don't experience illegal state
     // transitions.
     ConnectionState m_connectionState;
 };
 
 }
 
 #endif