MD Settings: add an aria-label to control indicators (often policy)

chrome/test/data/webui/settings/on_startup_browsertest.js

 // Copyright 2015 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.
 
 /** @fileoverview Runs Polymer OnStartup Settings tests. */
 
 GEN_INCLUDE(['settings_page_browsertest.js']);
 
 /**
   * Radio button enum values for restore on startup.
@@ skipping 36 matching lines @@
 TEST_F('OnStartupSettingsBrowserTest', 'uiTests', function() {
   /**
    * The prefs API that will get a fake implementation.
    * @type {!SettingsPrivate}
    */
   var settingsPrefs;
   var self = this;
 
   var restoreOnStartup = function() {
     return self.getPageElement('#onStartupRadioGroup').querySelector(
-        '.iron-selected').textContent.trim();
+        '.iron-selected').label;
   };
 
   suite('OnStartupHandler', function() {
     suiteSetup(function() {
       self.getPage('basic').set('pageVisibility.onStartup', true);
       Polymer.dom.flush();
 
       settingsPrefs = document.querySelector('settings-ui').$$(
           'settings-prefs');
       assertTrue(!!settingsPrefs);
@@ skipping 13 matching lines @@
     });
 
     test('open-specific', function() {
       settingsPrefs.set('prefs.session.restore_on_startup.value',
           RestoreOnStartupEnum.OPEN_SPECIFIC);
       assertEquals('Open a specific page or set of pages', restoreOnStartup());
     });
   });
   mocha.run();
 });