Remove some dead code from AXObjectCache

Source/core/accessibility/AXObjectCache.h

 /*
  * Copyright (C) 2003, 2006, 2007, 2008, 2009, 2010, 2011 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 140 matching lines @@
     void removeAXID(AXObject*);
     bool isIDinUse(AXID id) const { return m_idsInUse.contains(id); }
 
     Element* rootAXEditableElement(Node*);
     const Element* rootAXEditableElement(const Node*);
     bool nodeIsTextControl(const Node*);
 
     AXID platformGenerateAXID() const;
     AXObject* objectFromAXID(AXID id) const { return m_objects.get(id); }
 
-    // Text marker utilities.
-    void textMarkerDataForVisiblePosition(TextMarkerData&, const VisiblePosition&);
-    VisiblePosition visiblePositionForTextMarkerData(TextMarkerData&);
-
     enum AXNotification {
         AXActiveDescendantChanged,
         AXAlert,
         AXAriaAttributeChanged,
         AXAutocorrectionOccured,
         AXBlur,
         AXCheckedStateChanged,
         AXChildrenChanged,
         AXFocusedUIElementChanged,
         AXHide,
@@ skipping 62 matching lines @@
     AXID getAXID(AXObject*);
 };
 
 bool nodeHasRole(Node*, const String& role);
 // This will let you know if aria-hidden was explicitly set to false.
 bool isNodeAriaVisible(Node*);
 
 }
 
 #endif