[Oilpan] [Reland] Migrate classes under core/fetch to Oilpan heap

Source/core/loader/DocumentLoader.cpp

 /*
  * Copyright (C) 2006, 2007, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2011 Google 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.
@@ skipping 584 matching lines @@
     // It never makes sense to have a document loader that is detached from its
     // frame have any loads active, so go ahead and kill all the loads.
     stopLoading();
 
     // If that load cancellation triggered another detach, leave.
     // (fast/frames/detach-frame-nested-no-crash.html is an example of this.)
     if (!m_frame)
         return;
 
     m_fetcher->clearContext();
+
     m_applicationCacheHost->detachFromDocumentLoader();
     m_applicationCacheHost.clear();
     WeakIdentifierMap<DocumentLoader>::notifyObjectDestroyed(this);
     clearMainResourceHandle();
     m_frame = nullptr;
 }
 
 void DocumentLoader::clearMainResourceLoader()
 {
     m_loadingMainResource = false;
@@ skipping 206 matching lines @@
 {
     m_writer = createWriterFor(ownerDocument, init, mimeType(), m_writer ? m_writer->encoding() : emptyAtom, true, ForceSynchronousParsing);
     if (!source.isNull())
         m_writer->appendReplacingData(source);
     endWriting(m_writer.get());
 }
 
 DEFINE_WEAK_IDENTIFIER_MAP(DocumentLoader);
 
 } // namespace blink