Update HTMLCollection's named property getter to behave according to spec

Source/core/html/HTMLCollection.h

Index: Source/core/html/HTMLCollection.h
diff --git a/Source/core/html/HTMLCollection.h b/Source/core/html/HTMLCollection.h
index 5cf0419d4ba1eeb2845e5ec269067beb4299c5a8..94a5c2f8c298f0184bdfe83f35d7d914f89d3841 100644
--- a/Source/core/html/HTMLCollection.h
+++ b/Source/core/html/HTMLCollection.h
@@ -2,6 +2,7 @@
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2011, 2012 Apple Inc. All rights reserved.
+ * Copyright (C) 2014 Samsung Electronics. 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
@@ -46,6 +47,8 @@ public:
     unsigned length() const { return m_collectionIndexCache.nodeCount(*this); }
     Element* item(unsigned offset) const { return m_collectionIndexCache.nodeAt(*this, offset); }
     virtual Element* namedItem(const AtomicString& name) const;
+    bool namedPropertyQuery(const AtomicString&, ExceptionState&);
+    void namedPropertyEnumerator(Vector<String>& names, ExceptionState&);
 
     // Non-DOM API
     void namedItems(const AtomicString& name, Vector<RefPtr<Element> >&) const;
@@ -76,6 +79,7 @@ protected:
 
 private:
     Element* traverseNextElement(Element& previous, const ContainerNode& root) const;
+    virtual void supportedPropertyNames(Vector<String>& names);
 
     static void append(NodeCacheMap&, const AtomicString&, Element*);
     void invalidateIdNameCacheMaps() const