Fix the double-tap to click gesture in touch accessibility mode.

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 474 matching lines @@
   [cpp_enum_prefix_override="ax_description_from"] enum AXDescriptionFrom {
     uninitialized = 0,
     attribute,
     contents,
     placeholder,
     related_element
   };
 
   // Touch gestures on Chrome OS.
   enum AXGesture {
-    double_tap,
+    click,
     swipe_left_1,
     swipe_up_1,
     swipe_right_1,
     swipe_down_1,
     swipe_left_2,
     swipe_up_2,
     swipe_right_2,
     swipe_down_2,
     swipe_left_3,
     swipe_up_3,
     swipe_right_3,
     swipe_down_3,
     swipe_left_4,
     swipe_up_4,
     swipe_right_4,
     swipe_down_4
   };
 };