Use new is*Element() helper functions in DOM code

Source/core/dom/NodeRenderStyle.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2008 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 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,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  *
  */
 
 #ifndef NodeRenderStyle_h
 #define NodeRenderStyle_h
 
-#include "HTMLNames.h"
 #include "core/dom/Node.h"
 #include "core/dom/NodeRenderingTraversal.h"
+#include "core/html/HTMLOptGroupElement.h"
 #include "core/rendering/RenderObject.h"
 #include "core/rendering/style/RenderStyle.h"
 
 namespace WebCore {
 
 inline RenderStyle* Node::renderStyle() const
 {
     if (RenderObject* renderer = this->renderer())
         return renderer->style();
     // <option> and <optgroup> can be styled even though they never get renderers,
     // so they store their style internally and return it through nonRendererStyle().
     // We check here explicitly to avoid the virtual call in the common case.
-    if (hasTagName(HTMLNames::optgroupTag) || hasTagName(HTMLNames::optionTag))
+    if (isHTMLOptGroupElement(*this) || isHTMLOptionElement(this))
         return nonRendererStyle();
     return 0;
 }
 
 inline RenderStyle* Node::parentRenderStyle() const
 {
     ContainerNode* parent = NodeRenderingTraversal::parent(this);
     return parent ? parent->renderStyle() : 0;
 }
 
 }
 #endif