Have Frame::loader() return a reference

Source/core/loader/appcache/ApplicationCache.cpp

 /*
  * Copyright (C) 2008, 2009 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 39 matching lines @@
 
 void ApplicationCache::willDestroyGlobalObjectInFrame()
 {
     if (ApplicationCacheHost* cacheHost = applicationCacheHost())
         cacheHost->setApplicationCache(0);
     DOMWindowProperty::willDestroyGlobalObjectInFrame();
 }
 
 ApplicationCacheHost* ApplicationCache::applicationCacheHost() const
 {
-    if (!m_frame || !m_frame->loader()->documentLoader())
+    if (!m_frame || !m_frame->loader().documentLoader())
         return 0;
-    return m_frame->loader()->documentLoader()->applicationCacheHost();
+    return m_frame->loader().documentLoader()->applicationCacheHost();
 }
 
 unsigned short ApplicationCache::status() const
 {
     ApplicationCacheHost* cacheHost = applicationCacheHost();
     if (!cacheHost)
         return ApplicationCacheHost::UNCACHED;
     return cacheHost->status();
 }
 
@@ skipping 48 matching lines @@
     case ApplicationCacheHost::CACHED_EVENT:
         return EventTypeNames::cached;
     case ApplicationCacheHost::OBSOLETE_EVENT:
         return EventTypeNames::obsolete;
     }
     ASSERT_NOT_REACHED();
     return EventTypeNames::error;
 }
 
 } // namespace WebCore