Add hack so VoiceOver speaks updates to injected live regions.

content/browser/accessibility/browser_accessibility_manager.h

 // 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.
 
 #ifndef CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MANAGER_H_
 #define CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MANAGER_H_
 
 #include <vector>
 
 #include "base/containers/hash_tables.h"
@@ skipping 174 matching lines @@
  protected:
   BrowserAccessibilityManager(
       BrowserAccessibilityDelegate* delegate,
       BrowserAccessibilityFactory* factory);
 
   BrowserAccessibilityManager(
       const ui::AXTreeUpdate& initial_tree,
       BrowserAccessibilityDelegate* delegate,
       BrowserAccessibilityFactory* factory);
 
+  // Called at the end of updating the tree.
+  virtual void OnTreeUpdateFinished() {}
+
  private:
   // The following states keep track of whether or not the
   // on-screen keyboard is allowed to be shown.
   enum OnScreenKeyboardState {
     // Never show the on-screen keyboard because this tab is hidden.
     OSK_DISALLOWED_BECAUSE_TAB_HIDDEN,
 
     // This tab was just shown, so don't pop-up the on-screen keyboard if a
     // text field gets focus that wasn't the result of an explicit touch.
     OSK_DISALLOWED_BECAUSE_TAB_JUST_APPEARED,
@@ skipping 43 matching lines @@
 
   // The on-screen keyboard state.
   OnScreenKeyboardState osk_state_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserAccessibilityManager);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MANAGER_H_