Oilpan: avoid invoking some no-op finalizers.

Source/core/css/StyleSheetList.h

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2006, 2007 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,
@@ skipping 16 matching lines @@
 #include "wtf/Forward.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefCounted.h"
 #include "wtf/Vector.h"
 
 namespace blink {
 
 class HTMLStyleElement;
 class StyleSheet;
 
-class StyleSheetList : public RefCountedWillBeGarbageCollectedFinalized<StyleSheetList>, public ScriptWrappable {
+class StyleSheetList final : public RefCountedWillBeGarbageCollected<StyleSheetList>, public ScriptWrappable {
+    DECLARE_EMPTY_DESTRUCTOR_WILL_BE_REMOVED(StyleSheetList);
     DEFINE_WRAPPERTYPEINFO();
 public:
     static PassRefPtrWillBeRawPtr<StyleSheetList> create(TreeScope* treeScope) { return adoptRefWillBeNoop(new StyleSheetList(treeScope)); }
-    ~StyleSheetList();
 
     unsigned length();
     StyleSheet* item(unsigned index);
 
     HTMLStyleElement* getNamedItem(const AtomicString&) const;
 
     Document* document() { return m_treeScope ? &m_treeScope->document() : 0; }
 
 #if !ENABLE(OILPAN)
     void detachFromDocument();
 #endif
 
     CSSStyleSheet* anonymousNamedGetter(const AtomicString&);
 
     void trace(Visitor*);
 
 private:
-    StyleSheetList(TreeScope*);
+    explicit StyleSheetList(TreeScope*);
     const WillBeHeapVector<RefPtrWillBeMember<StyleSheet> >& styleSheets();
 
     RawPtrWillBeMember<TreeScope> m_treeScope;
 #if !ENABLE(OILPAN)
     Vector<RefPtr<StyleSheet> > m_detachedStyleSheets;
 #endif
 };
 
 } // namespace blink
 
 #endif // StyleSheetList_h