Revert of Move ThreadableLoader to Oilpan heap (2/3)

third_party/WebKit/Source/core/xmlhttprequest/XMLHttpRequest.cpp

 /*
  *  Copyright (C) 2004, 2006, 2008 Apple Inc. All rights reserved.
  *  Copyright (C) 2005-2007 Alexey Proskuryakov <ap@webkit.org>
  *  Copyright (C) 2007, 2008 Julien Chaffraix <jchaffraix@webkit.org>
  *  Copyright (C) 2008, 2011 Google Inc. All rights reserved.
  *  Copyright (C) 2012 Intel Corporation
  *
  *  This library is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU Lesser General Public
  *  License as published by the Free Software Foundation; either
@@ skipping 1006 matching lines @@
     if (!m_loader)
         return true;
 
     // Cancelling the ThreadableLoader m_loader may result in calling
     // window.onload synchronously. If such an onload handler contains open()
     // call on the same XMLHttpRequest object, reentry happens.
     //
     // If, window.onload contains open() and send(), m_loader will be set to
     // non 0 value. So, we cannot continue the outer open(). In such case,
     // just abort the outer open() by returning false.
-    ThreadableLoader* loader = m_loader.release();
+    std::unique_ptr<ThreadableLoader> loader = std::move(m_loader);
     loader->cancel();
 
     // If abort() called internalAbort() and a nested open() ended up
     // clearing the error flag, but didn't send(), make sure the error
     // flag is still set.
     bool newLoadStarted = m_loader.get();
     if (!newLoadStarted)
         m_error = true;
 
     return !newLoadStarted;
@@ skipping 660 matching lines @@
 
 ExecutionContext* XMLHttpRequest::getExecutionContext() const
 {
     return ActiveDOMObject::getExecutionContext();
 }
 
 DEFINE_TRACE(XMLHttpRequest)
 {
     visitor->trace(m_responseBlob);
     visitor->trace(m_responseLegacyStream);
-    visitor->trace(m_loader);
     visitor->trace(m_responseDocument);
     visitor->trace(m_responseDocumentParser);
     visitor->trace(m_responseArrayBuffer);
     visitor->trace(m_progressEventThrottle);
     visitor->trace(m_upload);
     visitor->trace(m_blobLoader);
     XMLHttpRequestEventTarget::trace(visitor);
     DocumentParserClient::trace(visitor);
     ActiveDOMObject::trace(visitor);
 }
 
 DEFINE_TRACE_WRAPPERS(XMLHttpRequest)
 {
     visitor->traceWrappers(m_responseBlob);
     visitor->traceWrappers(m_responseLegacyStream);
     visitor->traceWrappers(m_responseDocument);
     visitor->traceWrappers(m_responseArrayBuffer);
 }
 
 } // namespace blink