ChromeOS OOBE: Add ARIA-labels for OOBE screens.

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 10 matching lines @@
     /**
      * List of languages/keyboards to display
      * @type {!Array<I18nMenuItem>}
      */
     items: {
       type: Array,
       observer: 'onItemsChanged_',
     },
 
     /**
-     * Accessibility label.
-     * @type {!string}
+     * ARIA-label for the selection menu.
      */
-    label: {
-      type: String,
-    },
+    ariaLabel: String,
   },
 
   /**
    * Mapping from item id to item.
    * @type {!Map<string,I18nMenuItem>}
    */
   idToItem_: null,
 
   /**
    * @param {string} value Option value.
    * @private
    */
   onSelected_: function(value) {
     this.fire('select-item', this.idToItem_.get(value));
   },
 
   onItemsChanged_: function(items) {
     this.idToItem_ = new Map();
     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));
   },
 });
 })();