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

Source/WebCore/loader/FrameLoader.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2008 Alp Toker <alp@atoker.com>
  * Copyright (C) Research In Motion Limited 2009. All rights reserved.
  * Copyright (C) 2011 Kris Jordan <krisjordan@gmail.com>
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ skipping 1102 matching lines @@
         stateMachine()->advanceTo(FrameLoaderStateMachine::CommittedFirstRealLoad);
     }
 }
 
 void FrameLoader::prepareForLoadStart()
 {
     m_progressTracker->progressStarted();
     m_client->dispatchDidStartProvisionalLoad();
 
     // Notify accessibility.
-    if (AXObjectCache* cache = m_frame->document()->existingAXObjectCache()) {
+    if (AXObjectCache::accessibilityEnabled()) {
         AXObjectCache::AXLoadingEvent loadingEvent = loadType() == FrameLoadTypeReload ? AXObjectCache::AXLoadingReloaded : AXObjectCache::AXLoadingStarted;
-        cache->frameLoadingEventNotification(m_frame, loadingEvent);
+        m_frame->document()->axObjectCache()->frameLoadingEventNotification(m_frame, loadingEvent);
     }
 }
 
 void FrameLoader::setupForReplace()
 {
     m_client->revertToProvisionalState(m_documentLoader.get());
     setState(FrameStateProvisional);
     m_provisionalDocumentLoader = m_documentLoader;
     m_documentLoader = 0;
     detachChildren();
@@ skipping 1066 matching lines @@
 
             if (settings->needsDidFinishLoadOrderQuirk()) {
                 m_progressTracker->progressCompleted();
                 if (Page* page = m_frame->page()) {
                     if (m_frame == page->mainFrame())
                         page->resetRelevantPaintedObjectCounter();
                 }
             }
 
             // Notify accessibility.
-            if (AXObjectCache* cache = m_frame->document()->existingAXObjectCache())
-                cache->frameLoadingEventNotification(m_frame, loadingEvent);
+            if (AXObjectCache::accessibilityEnabled())
+                m_frame->document()->axObjectCache()->frameLoadingEventNotification(m_frame, loadingEvent);
 
             return;
         }
         
         case FrameStateComplete:
             m_loadType = FrameLoadTypeStandard;
             frameLoadCompleted();
             return;
     }
 
@@ skipping 1209 matching lines @@
     FloatRect newWindowRect = DOMWindow::adjustWindowRect(page, windowRect);
 
     page->chrome()->setWindowRect(newWindowRect);
     page->chrome()->show();
 
     created = true;
     return frame;
 }
 
 } // namespace WebCore