ChromeOS: Update browser option UI for automatic timezone detection.

chrome/browser/ui/webui/options/chromeos/date_time_options_browsertest.js

 // 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.
 
 GEN_INCLUDE(['chrome/browser/ui/webui/options/options_browsertest_base.js']);
 
 GEN('#if defined(OS_CHROMEOS)');
 
 /**
  * DateTimeOptionsWebUITest tests the date and time section of the options page.
  * @constructor
  * @extends {testing.Test}
  */
 function DateTimeOptionsWebUITest() {}
 
 DateTimeOptionsWebUITest.prototype = {
   __proto__: OptionsBrowsertestBase.prototype,
 
   /**
    * Browse to date/time options.
    * @override
    */
   browsePreload: 'chrome://settings-frame/search#date',
 };
 
 TEST_F('DateTimeOptionsWebUITest', 'testShowSetTimeButton', function() {
   assertEquals(this.browsePreload, document.location.href);
 
-  // Hide label and show button.
+  // Show button.
   BrowserOptions.setCanSetTime(true);
-  expectTrue($('time-synced-explanation').hidden);
   expectFalse($('set-time').hidden);
 
-  // Show label and hide button.
+  // Hide button.
   BrowserOptions.setCanSetTime(false);
-  expectFalse($('time-synced-explanation').hidden);
   expectTrue($('set-time').hidden);
 });
 
 GEN('#endif');