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

Source/core/accessibility/AXMenuListPopup.cpp

 /*
  * Copyright (C) 2010 Apple 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 48 matching lines @@
     return m_parent->isEnabled();
 }
 
 bool AXMenuListPopup::computeAccessibilityIsIgnored() const
 {
     return accessibilityIsIgnoredByDefault();
 }
 
 AXMenuListOption* AXMenuListPopup::menuListOptionAXObject(HTMLElement* element) const
 {
-    if (!element->hasTagName(optionTag))
+    ASSERT(element);
+    if (!isHTMLOptionElement(*element))
         return 0;
 
     AXObject* object = document()->axObjectCache()->getOrCreate(MenuListOptionRole);
     ASSERT_WITH_SECURITY_IMPLICATION(object->isMenuListOption());
 
     AXMenuListOption* option = toAXMenuListOption(object);
     option->setElement(element);
 
     return option;
 }
@@ skipping 57 matching lines @@
     ASSERT_ARG(optionIndex, optionIndex < static_cast<int>(m_children.size()));
 
     AXObjectCache* cache = axObjectCache();
     RefPtr<AXObject> child = m_children[optionIndex].get();
 
     cache->postNotification(child.get(), document(), AXObjectCache::AXFocusedUIElementChanged, true, PostSynchronously);
     cache->postNotification(child.get(), document(), AXObjectCache::AXMenuListItemSelected, true, PostSynchronously);
 }
 
 } // namespace WebCore