Revert of Move ThreadableLoader to Oilpan heap (3/3)

third_party/WebKit/Source/core/loader/DocumentThreadableLoader.cpp

 /*
  * Copyright (C) 2011, 2012 Google Inc. All rights reserved.
  * Copyright (C) 2013, Intel Corporation
  *
  * 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 323 matching lines @@
             ResourceLoaderOptions preflightOptions = m_actualOptions;
             preflightOptions.allowCredentials = DoNotAllowStoredCredentials;
             loadRequest(preflightRequest, preflightOptions);
         }
     }
 }
 
 DocumentThreadableLoader::~DocumentThreadableLoader()
 {
     CHECK(!m_client);
-    DCHECK(!resource());
+    DCHECK(!m_resource);
 }
 
 void DocumentThreadableLoader::overrideTimeout(unsigned long timeoutMilliseconds)
 {
     ASSERT(m_async);
 
     // |m_requestStartedSeconds| == 0.0 indicates loading is already finished
     // and |m_timeoutTimer| is already stopped, and thus we do nothing for such
     // cases. See https://crbug.com/551663 for details.
     if (m_requestStartedSeconds <= 0.0)
@@ skipping 609 matching lines @@
 }
 
 Document& DocumentThreadableLoader::document() const
 {
     ASSERT(m_document);
     return *m_document;
 }
 
 DEFINE_TRACE(DocumentThreadableLoader)
 {
+    visitor->trace(m_resource);
     visitor->trace(m_document);
     ThreadableLoader::trace(visitor);
-    ResourceOwner<RawResource>::trace(visitor);
 }
 
 } // namespace blink