Add hack so VoiceOver speaks updates to injected live regions.

content/browser/accessibility/browser_accessibility_manager_mac.h

Index: content/browser/accessibility/browser_accessibility_manager_mac.h
diff --git a/content/browser/accessibility/browser_accessibility_manager_mac.h b/content/browser/accessibility/browser_accessibility_manager_mac.h
index c0576190ae6f7bae3882357989b3ffc19886d121..b601beb38eb72bbf015366b36c3c4c53524c9ad8 100644
--- a/content/browser/accessibility/browser_accessibility_manager_mac.h
+++ b/content/browser/accessibility/browser_accessibility_manager_mac.h
@@ -29,12 +29,17 @@ class CONTENT_EXPORT BrowserAccessibilityManagerMac
   NSView* parent_view() { return parent_view_; }
 
  private:
+  virtual void OnNodeCreationFinished(ui::AXNode* node) OVERRIDE;
+  virtual void OnTreeUpdateFinished() OVERRIDE;
+
   // This gives BrowserAccessibilityManager::Create access to the class
   // constructor.
   friend class BrowserAccessibilityManager;
 
   NSView* parent_view_;
 
+  bool created_live_region_;
+
   DISALLOW_COPY_AND_ASSIGN(BrowserAccessibilityManagerMac);
 };