Mac a11y: Add Help, TopLevelUIElement, and Window accessibility attributes.

ui/accessibility/ax_enums.idl

 // Copyright 2014 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.
 
 // These should be kept in sync with third_party/WebKit/public/web/WebAXEnums.h
 // until the Chromium and Blink trees are merged.
 [camel_case_enum_to_string=true] namespace ui {
 
   // For new entries to the following three enums, also add to
   // chrome/common/extensions/api/automation.idl.
@@ skipping 228 matching lines @@
     action,
     // Only used when invalid_state == invalid_state_other.
     aria_invalid_value,
     auto_complete,
     container_live_relevant,
     container_live_status,
     description,
     display,
     // Only present when different from parent.
     font_family,
+    help_text,
     html_tag,
     // Only present when different from parent.
     language,
     name,
     live_relevant,
     live_status,
     placeholder,
     role,
     shortcut,
     url,
@@ skipping 246 matching lines @@
     swipe_left_3,
     swipe_up_3,
     swipe_right_3,
     swipe_down_3,
     swipe_left_4,
     swipe_up_4,
     swipe_right_4,
     swipe_down_4
   };
 };