Revert of Cross-process iframe accessibility.

content/renderer/accessibility/blink_ax_tree_source.h

Index: content/renderer/accessibility/blink_ax_tree_source.h
diff --git a/content/renderer/accessibility/blink_ax_tree_source.h b/content/renderer/accessibility/blink_ax_tree_source.h
index c58ee81a6e85923c5066fa83a358c6a82e2c6bd1..007df071052f54192146ba5178236b13212c0ab0 100644
--- a/content/renderer/accessibility/blink_ax_tree_source.h
+++ b/content/renderer/accessibility/blink_ax_tree_source.h
@@ -18,12 +18,6 @@
  public:
   BlinkAXTreeSource(RenderFrameImpl* render_frame);
   virtual ~BlinkAXTreeSource();
-
-  // Call this to have BlinkAXTreeSource collect a mapping from
-  // node ids to the frame routing id for an out-of-process iframe during
-  // calls to SerializeNode.
-  void CollectChildFrameIdMapping(
-      std::map<int32, int>* node_to_frame_routing_id_map);
 
   // Walks up the ancestor chain to see if this is a descendant of the root.
   bool IsInTree(blink::WebAXObject node) const;
@@ -48,8 +42,6 @@
 
  private:
   RenderFrameImpl* render_frame_;
-  std::map<int32, int>* node_to_frame_routing_id_map_;
-
 };
 
 }  // namespace content