Have Frame::loader() return a reference

Source/web/FrameLoaderClientImpl.cpp

 /*
  * Copyright (C) 2009, 2012 Google Inc. All rights reserved.
  * Copyright (C) 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 669 matching lines @@
 
     if (MIMETypeRegistry::isSupportedNonImageMIMEType(mimeType))
         return ObjectContentFrame;
 
     return ObjectContentNone;
 }
 
 PassOwnPtr<WebPluginLoadObserver> FrameLoaderClientImpl::pluginLoadObserver()
 {
     WebDataSourceImpl* ds = WebDataSourceImpl::fromDocumentLoader(
-        m_webFrame->frame()->loader()->activeDocumentLoader());
+        m_webFrame->frame()->loader().activeDocumentLoader());
     if (!ds) {
         // We can arrive here if a popstate event handler detaches this frame.
         // FIXME: Remove this code once http://webkit.org/b/36202 is fixed.
         ASSERT(!m_webFrame->frame()->page());
         return nullptr;
     }
     return ds->releasePluginLoadObserver();
 }
 
 WebCookieJar* FrameLoaderClientImpl::cookieJar() const
@@ skipping 66 matching lines @@
     return adoptPtr(m_webFrame->client()->createServiceWorkerProvider(m_webFrame, client.leakPtr()));
 }
 
 void FrameLoaderClientImpl::didStopAllLoaders()
 {
     if (m_webFrame->client())
         m_webFrame->client()->didAbortLoading(m_webFrame);
 }
 
 } // namespace WebKit