Use isHTML*Element() helpers more in the accessibility code

Source/core/accessibility/AXTable.cpp

 /*
  * Copyright (C) 2008 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
@@ skipping 88 matching lines @@
     if (node() && node()->rendererIsEditable())
         return true;
 
     // This employs a heuristic to determine if this table should appear.
     // Only "data" tables should be exposed as tables.
     // Unfortunately, there is no good way to determine the difference
     // between a "layout" table and a "data" table.
 
     RenderTable* table = toRenderTable(m_renderer);
     Node* tableNode = table->node();
-    if (!tableNode || !tableNode->hasTagName(tableTag))
+    if (!isHTMLTableElement(tableNode))
         return false;
 
     // if there is a caption element, summary, THEAD, or TFOOT section, it's most certainly a data table
     HTMLTableElement* tableElement = toHTMLTableElement(tableNode);
     if (!tableElement->summary().isEmpty() || tableElement->tHead() || tableElement->tFoot() || tableElement->caption())
         return true;
 
     // if someone used "rules" attribute than the table should appear
     if (!tableElement->rules().isEmpty())
         return true;
@@ skipping 408 matching lines @@
 {
     if (!isAXTable())
         return AXRenderObject::title();
 
     String title;
     if (!m_renderer)
         return title;
 
     // see if there is a caption
     Node* tableElement = m_renderer->node();
-    if (tableElement && tableElement->hasTagName(tableTag)) {
+    if (isHTMLTableElement(tableElement)) {
         HTMLTableCaptionElement* caption = toHTMLTableElement(tableElement)->caption();
         if (caption)
             title = caption->innerText();
     }
 
     // try the standard
     if (title.isEmpty())
         title = AXRenderObject::title();
 
     return title;
 }
 
 } // namespace WebCore