Update browser cache of accessibility tree on renderer sub-tree changes....

chrome/browser/browser_accessibility_manager_win.h

Index: chrome/browser/browser_accessibility_manager_win.h
===================================================================
--- chrome/browser/browser_accessibility_manager_win.h	(revision 57122)
+++ chrome/browser/browser_accessibility_manager_win.h	(working copy)
@@ -10,6 +10,9 @@
 #include <atlcom.h>
 #include <oleacc.h>
 
+#include <hash_map>
+#include <vector>
+
 #include "base/hash_tables.h"
 #include "base/scoped_comptr_win.h"
 #include "base/scoped_ptr.h"
@@ -32,6 +35,7 @@
   virtual ~BrowserAccessibilityDelegate() {}
   virtual void SetAccessibilityFocus(int acc_obj_id) = 0;
   virtual void AccessibilityDoDefaultAction(int acc_obj_id) = 0;
+  virtual void AccessibilityObjectChildrenChangeAck() = 0;
 };
 
 // Manages a tree of BrowserAccessibility objects.
@@ -48,6 +52,9 @@
   // Return a pointer to the root of the tree, does not make a new reference.
   BrowserAccessibility* GetRoot();
 
+  // Removes the BrowserAccessibility child_id from the manager.
+  void Remove(LONG child_id);
+
   // Return a pointer to the object corresponding to the given child_id,
   // does not make a new reference.
   BrowserAccessibility* GetFromChildID(LONG child_id);
@@ -69,16 +76,22 @@
   // Tell the renderer to do the default action for this node.
   void DoDefaultAction(const BrowserAccessibility& node);
 
-  // Called when the renderer process has notified us of a focus or state
-  // change. Send a notification to MSAA clients of the change.
+  // Called when the renderer process has notified us of a focus, state,
+  // or children change. Send a notification to MSAA clients of the change.
   void OnAccessibilityFocusChange(int acc_obj_id);
   void OnAccessibilityObjectStateChange(int acc_obj_id);
+  void OnAccessibilityObjectChildrenChange(
+      const std::vector<webkit_glue::WebAccessibility>& acc_changes);
 
  private:
+  // Returns the next MSAA child id.
+  static LONG GetNextChildID();
+
   // Recursively build a tree of BrowserAccessibility objects from
   // the WebAccessibility tree received from the renderer process.
   BrowserAccessibility* CreateAccessibilityTree(
       BrowserAccessibility* parent,
+      int child_id,
       const webkit_glue::WebAccessibility& src,
       int index_in_parent);