Revert 146726 "AXObjectCache gets recreated during document tear..."

Source/WebCore/editing/DeleteFromTextNodeCommand.cpp

 /*
  * Copyright (C) 2005, 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 39 matching lines @@
 
     if (!m_node->isContentEditable(Node::UserSelectAllIsAlwaysNonEditable))
         return;
 
     ExceptionCode ec = 0;
     m_text = m_node->substringData(m_offset, m_count, ec);
     if (ec)
         return;
     
     // Need to notify this before actually deleting the text
-    if (AXObjectCache* cache = document()->existingAXObjectCache())
-        cache->nodeTextChangeNotification(m_node.get(), AXObjectCache::AXTextDeleted, m_offset, m_text);
+    if (AXObjectCache::accessibilityEnabled())
+        document()->axObjectCache()->nodeTextChangeNotification(m_node.get(), AXObjectCache::AXTextDeleted, m_offset, m_text);
 
     m_node->deleteData(m_offset, m_count, ec);
 }
 
 void DeleteFromTextNodeCommand::doUnapply()
 {
     ASSERT(m_node);
 
     if (!m_node->rendererIsEditable())
         return;
 
     m_node->insertData(m_offset, m_text, IGNORE_EXCEPTION);
 
-    if (AXObjectCache* cache = document()->existingAXObjectCache())
-        cache->nodeTextChangeNotification(m_node.get(), AXObjectCache::AXTextInserted, m_offset, m_text);
+    if (AXObjectCache::accessibilityEnabled())
+        document()->axObjectCache()->nodeTextChangeNotification(m_node.get(), AXObjectCache::AXTextInserted, m_offset, m_text);
 }
 
 #ifndef NDEBUG
 void DeleteFromTextNodeCommand::getNodesInCommand(HashSet<Node*>& nodes)
 {
     addNodeAndDescendants(m_node.get(), nodes);
 }
 #endif
 
 } // namespace WebCore