Refactors parse_html_subset() into i18n_behavior.

chrome/test/data/webui/md_user_manager/create_profile_tests.js

 // Copyright 2016 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.define('user_manager.create_profile_tests', function() {
   /** @return {!CreateProfileElement} */
   function createElement() {
     PolymerTest.clearBody();
     var createProfileElement = document.createElement('create-profile');
     document.body.appendChild(createProfileElement);
@@ skipping 65 matching lines @@
 
       test('Sentinel item is the initially selected item', function() {
         return browserProxy.whenCalled('getSignedInUsers').then(function() {
           // Simulate checking the checkbox.
           MockInteractions.tap(createProfileElement.$$('paper-checkbox'));
           Polymer.dom.flush();
 
           var dropdownMenu = createProfileElement.$$('paper-dropdown-menu');
           var paperMenu = dropdownMenu.querySelector('paper-menu');
           assertEquals(createProfileElement.i18n('selectAnAccount'),
-                       paperMenu.selectedItem.textContent.trim());
+                       [paperMenu.selectedItem.textContent.trim()]);
         });
       });
 
       test('Name is non-empty by default', function() {
         assertEquals('profile name', createProfileElement.$.nameInput.value);
       });
 
       test('Create button is disabled if name is empty or invalid', function() {
         assertEquals('profile name', createProfileElement.$.nameInput.value);
         assertFalse(createProfileElement.$.nameInput.invalid);
@@ skipping 290 matching lines @@
       test('Create button is disabled', function() {
         assertTrue(createProfileElement.$.save.disabled);
       });
     });
   }
 
   return {
     registerTests: registerTests,
   };
 });