Oilpan: move HistoryItem to the heap.

Source/web/WebHistoryItem.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 202 matching lines @@
 
     const Vector<String>& referencedFilePaths = m_private->getReferencedFilePaths();
     for (size_t i = 0; i < referencedFilePaths.size(); ++i)
         filePaths.add(referencedFilePaths[i]);
 
     Vector<String> results;
     copyToVector(filePaths, results);
     return results;
 }
 
-WebHistoryItem::WebHistoryItem(const PassRefPtr<HistoryItem>& item)
+WebHistoryItem::WebHistoryItem(const PassRefPtrWillBeRawPtr<HistoryItem>& item)
     : m_private(item)
 {
 }
 
-WebHistoryItem& WebHistoryItem::operator=(const PassRefPtr<HistoryItem>& item)
+WebHistoryItem& WebHistoryItem::operator=(const PassRefPtrWillBeRawPtr<HistoryItem>& item)
 {
     m_private = item;
     return *this;
 }
 
-WebHistoryItem::operator PassRefPtr<HistoryItem>() const
+WebHistoryItem::operator PassRefPtrWillBeRawPtr<HistoryItem>() const
 {
     return m_private.get();
 }
 
 } // namespace blink