Oilpan: Make the Node hierarchy RefCountedGarbageCollected instead of TreeShared.

Source/core/dom/StyleEngine.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
@@ skipping 72 matching lines @@
         {
         }
     };
 
     friend class IgnoringPendingStylesheet;
 
     static PassOwnPtrWillBeRawPtr<StyleEngine> create(Document& document) { return adoptPtrWillBeNoop(new StyleEngine(document)); }
 
     ~StyleEngine();
 
+#if !ENABLE(OILPAN)
     void detachFromDocument();
+#endif
 
     const WillBeHeapVector<RefPtrWillBeMember<StyleSheet> >& styleSheetsForStyleSheetList(TreeScope&);
     const WillBeHeapVector<RefPtrWillBeMember<CSSStyleSheet> >& activeAuthorStyleSheets() const;
 
     const WillBeHeapVector<RefPtrWillBeMember<CSSStyleSheet> >& documentAuthorStyleSheets() const { return m_authorStyleSheets; }
     const WillBeHeapVector<RefPtrWillBeMember<CSSStyleSheet> >& injectedAuthorStyleSheets() const;
 
     const WillBeHeapVector<RefPtrWillBeMember<StyleSheet> > activeStyleSheetsForInspector() const;
 
     void modifiedStyleSheet(StyleSheet*);
@@ skipping 144 matching lines @@
 
     RefPtrWillBeMember<CSSFontSelector> m_fontSelector;
 
     WillBeHeapHashMap<AtomicString, RawPtrWillBeMember<StyleSheetContents> > m_textToSheetCache;
     WillBeHeapHashMap<RawPtrWillBeMember<StyleSheetContents>, AtomicString> m_sheetToTextCache;
 };
 
 }
 
 #endif