[oilpan] The Node hierarchy should have correct accept method chains

Source/core/html/shadow/HTMLContentElement.h

 /*
  * Copyright (C) 2011 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 36 matching lines @@
 
     void setSelect(const AtomicString&);
     const AtomicString& select() const;
 
     virtual MatchType matchTypeFor(Node*) OVERRIDE;
     virtual const CSSSelectorList& selectorList() OVERRIDE;
     virtual Type insertionPointType() const OVERRIDE { return ContentInsertionPoint; }
     virtual bool canAffectSelector() const OVERRIDE { return true; }
     virtual bool isSelectValid();
 
-    virtual void acceptHeapVisitor(Visitor*) const OVERRIDE;
-
 protected:
     HTMLContentElement(const QualifiedName&, Handle<Document>);
 
+    virtual void acceptHeapVisitor(Visitor*) const OVERRIDE;
+
 private:
     virtual void parseAttribute(const QualifiedName&, const AtomicString&) OVERRIDE;
     void ensureSelectParsed();
     bool validateSelect() const;
 
     bool m_shouldParseSelectorList;
     bool m_isValidSelector;
     CSSSelectorList m_selectorList;
 };
 
@@ skipping 17 matching lines @@
 
 inline Result<HTMLContentElement> toHTMLContentElement(Node* node)
 {
     ASSERT_WITH_SECURITY_IMPLICATION(!node || isHTMLContentElement(node));
     return adoptRawResult(static_cast<HTMLContentElement*>(node));
 }
 
 }
 
 #endif