Add 5 experimental accessibility features on Chrome OS.

chrome/browser/resources/options/browser_options.js

 // 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.
 
 cr.exportPath('options');
 
 /**
  * @typedef {{actionLinkText: (string|undefined),
  *            childUser: (boolean|undefined),
  *            hasError: (boolean|undefined),
@@ skipping 710 matching lines @@
             $('accessibility-screen-magnifier-check').getAttribute('pref'),
             updateScreenMagnifierCenterFocus);
 
         var updateDelayDropdown = function() {
           $('accessibility-autoclick-dropdown').disabled =
               !$('accessibility-autoclick-check').checked;
         };
         Preferences.getInstance().addEventListener(
             $('accessibility-autoclick-check').getAttribute('pref'),
             updateDelayDropdown);
+        $('experimental_accessibility_features').hidden =
+            !loadTimeData.getBoolean('enableExperimentalAccessibilityFeatures');
       }
 
       // Display management section (CrOS only).
       if (cr.isChromeOS) {
         $('display-options').onclick = function(event) {
           PageManager.showPageByName('display');
           chrome.send('coreOptionsUserMetricsAction',
                       ['Options_Display']);
         };
       }
@@ skipping 1591 matching lines @@
       if (section)
         section.hidden = true;
     };
   }
 
   // Export
   return {
     BrowserOptions: BrowserOptions
   };
 });