ChromeOS OOBE: fix focus flow in MD-OOBE.

chrome/browser/resources/chromeos/login/oobe_a11y_option.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.
 
 Polymer({
   is: 'oobe-a11y-option',
 
   properties: {
     /**
      * If paper-toggle-button is checked.
      */
     checked: {
       type: Boolean,
     },
 
     /**
      * Chrome message handling this option.
      */
     chromeMessage: {
       type: String,
     },
 
     /**
      * ARIA-label for the button.
      */
-    ariaLabel: String,
+    label: String,

[stevenjb, 2017/02/14 01:21:32]

Why does this need to be renamed here and elsewhere? It seemed more clear
before.

[Alexander Alekseev, 2017/02/14 11:59:27]

Because otherwise it will become aria-label attribute of <oobe-a11y-option> tag
itself in addition to actual input element inside it. So ChromeVox will
pronounce it twice (sometimes).

[stevenjb, 2017/02/14 17:35:34]

I see. I'm not super fond of just 'label' for something that will only be used
for aria, maybe 'labelForAria'?

[Alexander Alekseev, 2017/02/14 23:41:17]

Done.

+  },
+
+  focus: function() {
+    this.$.button.focus();
   },
 });