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_) {
+    [browser_accessibility_cocoa_ detach];
+    [browser_accessibility_cocoa_ release];
+  }
+  browser_accessibility_cocoa_ = [[BrowserAccessibilityCocoa alloc]

[David Tseng, 2014/05/08 17:07:02]

Could you check for loss of VoiceOver when this code gets hit? (both when
VoiceOver's cursor is over focusable and non-focusable items).

[dmazzoni, 2014/05/08 21:02:05]

Works great when the cursor is over a focusable item, nothing is spoken and no
context is lost.

When the cursor is over a non-focusable item, it's silent, but when you try to
navigate again it snaps you back to the last focused item first. Not idea, but I
think it's an okay trade-off.

Remember we can lose this hack when the next OS X version comes out.

+      initWithObject:this];
+}
+
 BrowserAccessibilityCocoa* BrowserAccessibility::ToBrowserAccessibilityCocoa() {
   return static_cast<BrowserAccessibilityMac*>(this)->
       native_view();
 }
 
 }  // namespace content