ChromeOS OOBE: More accessibility fixes.

chrome/browser/resources/chromeos/login/oobe_i18n_dropdown.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 class definition for 'oobe-i18n-dropdown'.
  */
 (function() {
 
 
@@ skipping 11 matching lines @@
      * List of languages/keyboards to display
      * @type {!Array<I18nMenuItem>}
      */
     items: {
       type: Array,
       observer: 'onItemsChanged_',
     },
 
     /**
      * ARIA-label for the selection menu.
+     *
+     * Note that we are not using "aria-label" property here, because
+     * we want to pass the label value but not actually declare it as an
+     * ARIA property anywhere but the actual target element.
      */
     labelForAria: String,
   },
 
   /**
    * Mapping from item id to item.
    * @type {!Map<string,I18nMenuItem>}
    */
   idToItem_: null,
 
@@ skipping 14 matching lines @@
     for (var i = 0; i < items.length; ++i) {
       var item = items[i];
       this.idToItem_.set(item.value, item);
     }
     Oobe.setupSelect(this.$.select,
                        items,
                        this.onSelected_.bind(this));
   },
 });
 })();