Add a use counter for Attr.prototype.cloneNode()

third_party/WebKit/Source/core/dom/Attr.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Peter Kelly (pmk@post.com)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2009, 2010, 2012 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
@@ skipping 99 matching lines @@
 
 void Attr::setNodeValue(const String& v)
 {
     // Attr uses AtomicString type for its value to save memory as there
     // is duplication among Elements' attributes values.
     setValue(AtomicString(v));
 }
 
 PassRefPtrWillBeRawPtr<Node> Attr::cloneNode(bool /*deep*/)
 {
+    UseCounter::count(document(), UseCounter::AttrCloneNode);
     return adoptRefWillBeNoop(new Attr(document(), m_name, value()));
 }
 
 void Attr::detachFromElementWithValue(const AtomicString& value)
 {
     ASSERT(m_element);
     m_standaloneValueOrAttachedLocalName = value;
     m_element = nullptr;
 }
 
 void Attr::attachToElement(Element* element, const AtomicString& attachedLocalName)
 {
     ASSERT(!m_element);
     m_element = element;
     m_standaloneValueOrAttachedLocalName = attachedLocalName;
 }
 
 DEFINE_TRACE(Attr)
 {
     visitor->trace(m_element);
     Node::trace(visitor);
 }
 
 }