Add hack so VoiceOver speaks updates to injected live regions.

content/browser/accessibility/browser_accessibility_mac.mm

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import <Cocoa/Cocoa.h>
 
 #import "content/browser/accessibility/browser_accessibility_mac.h"
 
 #import "content/browser/accessibility/browser_accessibility_cocoa.h"
 #include "content/browser/accessibility/browser_accessibility_manager_mac.h"
@@ skipping 30 matching lines @@
   // reference to the cocoa object.
   [browser_accessibility_cocoa_ release];
   // Finally, it's safe to delete this since we've detached.
   delete this;
 }
 
 bool BrowserAccessibilityMac::IsNative() const {
   return true;
 }
 
+void BrowserAccessibilityMac::RecreateNativeObject() {
+  if (!browser_accessibility_cocoa_)
+    return;
+
+  // Preserve the children so that recreating the native object doesn't
+  // end up recreating the whole subtree.
+  base::scoped_nsobject<NSMutableArray> children;
+  [browser_accessibility_cocoa_ swapChildren:&children];
+  [browser_accessibility_cocoa_ detach];
+  [browser_accessibility_cocoa_ release];
+  browser_accessibility_cocoa_ = [[BrowserAccessibilityCocoa alloc]
+      initWithObject:this];
+  [browser_accessibility_cocoa_ swapChildren:&children];
+}
+
 BrowserAccessibilityCocoa* BrowserAccessibility::ToBrowserAccessibilityCocoa() {
   return static_cast<BrowserAccessibilityMac*>(this)->
       native_view();
 }
 
 }  // namespace content