Create OOBE screen for Waiting for Container ready

chrome/browser/resources/chromeos/login/oobe_screen_voice_interaction_value_prop.js

 // Copyright 2017 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 Oobe Voice Interaction Value Prop screen implementation.
  */
 
 login.createScreen('VoiceInteractionValuePropScreen',
     'voice-interaction-value-prop', function() {
   return {
 
+    /**
+     * Returns a control which should receive an initial focus.
+     */
+    get defaultControl() {
+      return $('voice-interaction-value-prop-md').getElement('continueButton');
+    },
+
     /** @Override */
     onBeforeShow: function(data) {
       var valueView = $('voice-interaction-value-prop-md').
           getElement('value-prop-view');
 
       valueView.addContentScripts([
           {
             name: 'stripLinks',
             matches: ['<all_urls>'],
             js: { code:
@@ skipping 15 matching lines @@
       }, {urls: ['<all_urls>'], types: ['main_frame']});
 
       var locale = loadTimeData.getString('locale');
       valueView.src = 'https://www.gstatic.com/opa-chromeos/oobe/' + locale
           + '/value_proposition.html';
 
       Oobe.getInstance().headerHidden = true;
     }
   };
 });