Use new is*Element() helper functions further more in HTML code

Source/core/html/HTMLTableElement.cpp

 /*
  * Copyright (C) 1997 Martin Jones (mjones@kde.org)
  *           (C) 1997 Torben Weis (weis@kde.org)
  *           (C) 1998 Waldo Bastian (bastian@kde.org)
  *           (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2008, 2010, 2011 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
@@ skipping 19 matching lines @@
 #include "HTMLNames.h"
 #include "bindings/v8/ExceptionState.h"
 #include "bindings/v8/ExceptionStatePlaceholder.h"
 #include "core/css/CSSImageValue.h"
 #include "core/css/CSSValuePool.h"
 #include "core/css/StylePropertySet.h"
 #include "core/dom/Attribute.h"
 #include "core/dom/ElementTraversal.h"
 #include "core/dom/ExceptionCode.h"
 #include "core/html/HTMLTableCaptionElement.h"
+#include "core/html/HTMLTableCellElement.h"
 #include "core/html/HTMLTableRowElement.h"
 #include "core/html/HTMLTableRowsCollection.h"
 #include "core/html/HTMLTableSectionElement.h"
 #include "core/html/parser/HTMLParserIdioms.h"
 #include "core/rendering/RenderTable.h"
 #include "wtf/StdLibExtras.h"
 
 namespace WebCore {
 
 using namespace HTMLNames;
@@ skipping 198 matching lines @@
         return;
     }
     row->remove(exceptionState);
 }
 
 void HTMLTableElement::setNeedsTableStyleRecalc() const
 {
     Element* element = ElementTraversal::next(*this, this);
     while (element) {
         element->setNeedsStyleRecalc(LocalStyleChange);
-        if (element->hasTagName(tdTag) || element->hasTagName(thTag))
+        if (isHTMLTableCellElement(*element))
             element = ElementTraversal::nextSkippingChildren(*element, this);
         else
             element = ElementTraversal::next(*element, this);
     }
 }
 
 static bool getBordersFromFrameAttributeValue(const AtomicString& value, bool& borderTop, bool& borderRight, bool& borderBottom, bool& borderLeft)
 {
     borderTop = false;
     borderRight = false;
@@ skipping 280 matching lines @@
 {
     return getAttribute(rulesAttr);
 }
 
 const AtomicString& HTMLTableElement::summary() const
 {
     return getAttribute(summaryAttr);
 }
 
 }