Remove more oilpan.

sky/engine/core/dom/TreeShared.h

 /*
  * Copyright (C) 2006, 2007, 2009, 2010, 2012 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 15 matching lines @@
 #include "wtf/MainThread.h"
 #include "wtf/Noncopyable.h"
 
 namespace blink {
 
 #if ENABLE(SECURITY_ASSERT)
 template<typename NodeType> class TreeShared;
 template<typename NodeType> void adopted(TreeShared<NodeType>*);
 #endif
 
-template<typename NodeType> class TreeShared : public DummyBase<NodeType> {
+template<typename NodeType> class TreeShared {
     WTF_MAKE_NONCOPYABLE(TreeShared);
 protected:
     TreeShared()
         : m_refCount(1)
 #if ENABLE(SECURITY_ASSERT)
         , m_deletionHasBegun(false)
 #if ENABLE(ASSERT)
         , m_inRemovedLastRefFunction(false)
         , m_adoptionIsRequired(true)
 #endif
@@ skipping 64 matching lines @@
 #if ENABLE(ASSERT)
     ASSERT(!object->m_inRemovedLastRefFunction);
     object->m_adoptionIsRequired = false;
 #endif
 }
 #endif
 
 }
 
 #endif // TreeShared.h