Introduce isHTMLLabelElement and toHTMLLabelElement

Source/core/accessibility/AccessibilityNodeObject.cpp

 /*
 * Copyright (C) 2012, Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 190 matching lines @@
         return selectElement->multiple() ? ListBoxRole : PopUpButtonRole;
     }
     if (node()->hasTagName(textareaTag))
         return TextAreaRole;
     if (headingLevel())
         return HeadingRole;
     if (node()->hasTagName(divTag))
         return DivRole;
     if (node()->hasTagName(pTag))
         return ParagraphRole;
-    if (node()->hasTagName(labelTag))
+    if (isHTMLLabelElement(node()))
         return LabelRole;
     if (node()->isFocusable())
         return GroupRole;
 
     return UnknownRole;
 }
 
 AccessibilityRole AccessibilityNodeObject::determineAriaRoleAttribute() const
 {
     const AtomicString& ariaRole = getAttribute(roleAttr);
@@ skipping 121 matching lines @@
     if (!element->isHTMLElement() || !toHTMLElement(element)->isLabelable())
         return 0;
 
     const AtomicString& id = element->getIdAttribute();
     if (!id.isEmpty()) {
         if (HTMLLabelElement* label = element->treeScope()->labelElementForId(id))
             return label;
     }
 
     for (Element* parent = element->parentElement(); parent; parent = parent->parentElement()) {
-        if (parent->hasTagName(labelTag))
-            return static_cast<HTMLLabelElement*>(parent);
+        if (isHTMLLabelElement(parent))
+            return toHTMLLabelElement(parent);
     }
 
     return 0;
 }
 
 AccessibilityObject* AccessibilityNodeObject::menuButtonForMenu() const
 {
     Element* menuItem = menuItemElementForMenu();
 
     if (menuItem) {
@@ skipping 1300 matching lines @@
         useTextUnderElement = true;
 
     if (useTextUnderElement) {
         String text = textUnderElement();
         if (!text.isEmpty())
             textOrder.append(AccessibilityText(text, ChildrenText));
     }
 }
 
 } // namespace WebCore