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

Source/core/dom/Notation.h

Index: Source/core/dom/Notation.h
diff --git a/Source/core/dom/Notation.h b/Source/core/dom/Notation.h
index 819ff101c54ea49fb82d67d520bd5869e78644af..baf8608d7b2537f8089124918ee0b9b210c18953 100644
--- a/Source/core/dom/Notation.h
+++ b/Source/core/dom/Notation.h
@@ -33,6 +33,8 @@ public:
     const String& publicId() const { return m_publicId; }
     const String& systemId() const { return m_systemId; }
 
+    virtual void acceptHeapVisitor(Visitor*) const OVERRIDE;
+
 private:
     Notation(Handle<Document>, const String& name, const String& publicId, const String& systemId);