Oilpan: enable appcache + move DocumentLoader to the heap.

Source/web/WebDataSourceImpl.cpp

 /*
  * Copyright (C) 2009 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 26 matching lines @@
 #include "public/platform/WebVector.h"
 
 namespace blink {
 
 static OwnPtr<WebPluginLoadObserver>& nextPluginLoadObserver()
 {
     DEFINE_STATIC_LOCAL(OwnPtr<WebPluginLoadObserver>, nextPluginLoadObserver, ());
     return nextPluginLoadObserver;
 }
 
-PassRefPtr<WebDataSourceImpl> WebDataSourceImpl::create(LocalFrame* frame, const ResourceRequest& request, const SubstituteData& data)
+PassRefPtrWillBeRawPtr<WebDataSourceImpl> WebDataSourceImpl::create(LocalFrame* frame, const ResourceRequest& request, const SubstituteData& data)
 {
-    return adoptRef(new WebDataSourceImpl(frame, request, data));
+    return adoptRefWillBeNoop(new WebDataSourceImpl(frame, request, data));
 }
 
 const WebURLRequest& WebDataSourceImpl::originalRequest() const
 {
     m_originalRequestWrapper.bind(DocumentLoader::originalRequest());
     return m_originalRequestWrapper;
 }
 
 const WebURLRequest& WebDataSourceImpl::request() const
 {
@@ skipping 93 matching lines @@
     // to wait to attach the WebPluginLoadObserver to that data source.
     if (request.url().isEmpty())
         return;
 
     ASSERT(nextPluginLoadObserver()->url() == WebURL(request.url()));
     m_pluginLoadObserver = nextPluginLoadObserver().release();
 }
 
 WebDataSourceImpl::~WebDataSourceImpl()
 {
+    // Verify that detachFromFrame() has been called.
+    ASSERT(!m_extraData);
+}
+
+void WebDataSourceImpl::detachFromFrame()
+{
+    RefPtrWillBeRawPtr<DocumentLoader> protect(this);
+
+    DocumentLoader::detachFromFrame();
+    m_extraData.clear();
+    m_pluginLoadObserver.clear();
+}
+
+DEFINE_TRACE(WebDataSourceImpl)
+{
+    DocumentLoader::trace(visitor);
 }
 
 } // namespace blink