Introduce isHTMLOptGroupElement and toHTMLOptGroupElement

Source/core/rendering/RenderMenuList.cpp

 /*
  * This file is part of the select element renderer in WebCore.
  *
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  *               2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * 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 381 matching lines @@
 
 String RenderMenuList::itemText(unsigned listIndex) const
 {
     HTMLSelectElement* select = selectElement();
     const Vector<HTMLElement*>& listItems = select->listItems();
     if (listIndex >= listItems.size())
         return String();
 
     String itemString;
     Element* element = listItems[listIndex];
-    if (element->hasTagName(optgroupTag))
-        itemString = static_cast<const HTMLOptGroupElement*>(element)->groupLabelText();
+    if (isHTMLOptGroupElement(element))
+        itemString = toHTMLOptGroupElement(element)->groupLabelText();
     else if (element->hasTagName(optionTag))
         itemString = toHTMLOptionElement(element)->textIndentedToRespectGroupLabel();
 
     applyTextTransform(style(), itemString, ' ');
     return itemString;
 }
 
 String RenderMenuList::itemLabel(unsigned) const
 {
     return String();
@@ skipping 25 matching lines @@
 {
     const Vector<HTMLElement*>& listItems = selectElement()->listItems();
     if (listIndex >= listItems.size())
         return false;
     HTMLElement* element = listItems[listIndex];
     if (!element->hasTagName(optionTag))
         return false;
 
     bool groupEnabled = true;
     if (Element* parentElement = element->parentElement()) {
-        if (parentElement->hasTagName(optgroupTag))
+        if (isHTMLOptGroupElement(parentElement))
             groupEnabled = !parentElement->isDisabledFormControl();
     }
     if (!groupEnabled)
         return false;
 
     return !element->isDisabledFormControl();
 }
 
 PopupMenuStyle RenderMenuList::itemStyle(unsigned listIndex) const
 {
@@ skipping 123 matching lines @@
 
 bool RenderMenuList::itemIsSeparator(unsigned listIndex) const
 {
     const Vector<HTMLElement*>& listItems = selectElement()->listItems();
     return listIndex < listItems.size() && listItems[listIndex]->hasTagName(hrTag);
 }
 
 bool RenderMenuList::itemIsLabel(unsigned listIndex) const
 {
     const Vector<HTMLElement*>& listItems = selectElement()->listItems();
-    return listIndex < listItems.size() && listItems[listIndex]->hasTagName(optgroupTag);
+    return listIndex < listItems.size() && isHTMLOptGroupElement(listItems[listIndex]);
 }
 
 bool RenderMenuList::itemIsSelected(unsigned listIndex) const
 {
     const Vector<HTMLElement*>& listItems = selectElement()->listItems();
     if (listIndex >= listItems.size())
         return false;
     HTMLElement* element = listItems[listIndex];
     return element->hasTagName(optionTag) && toHTMLOptionElement(element)->selected();
 }
 
 void RenderMenuList::setTextFromItem(unsigned listIndex)
 {
     setTextFromOption(selectElement()->listToOptionIndex(listIndex));
 }
 
 FontSelector* RenderMenuList::fontSelector() const
 {
     return document()->styleResolver()->fontSelector();
 }
 
 }