Convert Event#keyIdentifier (deprecated) to Event#key

ui/webui/resources/js/cr/ui/autocomplete_list.js

 // Copyright (c) 2012 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('cr.ui', function() {
   /** @const */ var ArrayDataModel = cr.ui.ArrayDataModel;
   /** @const */ var List = cr.ui.List;
   /** @const */ var ListItem = cr.ui.ListItem;
 
   /**
@@ skipping 221 matching lines @@
     /**
      * Handles input field key events that should be interpreted as autocomplete
      * commands.
      * @param {Event} event The keydown event.
      * @private
      */
     handleAutocompleteKeydown_: function(event) {
       if (this.hidden)
         return;
       var handled = false;
-      switch (event.keyIdentifier) {
-        case 'U+001B':  // Esc
+      switch (event.key) {
+        case 'Escape':
           this.suggestions = [];
           handled = true;
           break;
         case 'Enter':
           // If the user has already selected an item using the arrow keys then
           // presses Enter, keep |handled| = false, so the input field can
           // handle the event as well.
           this.handleEnterKeydown();
           break;
-        case 'Up':
-        case 'Down':
-          var newEvent = new Event(event.type);
-          newEvent.keyIdentifier = event.keyIdentifier;
-          this.dispatchEvent(newEvent);
+        case 'ArrowUp':
+        case 'ArrowDown':
+          this.dispatchEvent(new KeyboardEvent(event.type, event));
           handled = true;
           break;
       }
       // Don't let arrow keys affect the text field, or bubble up to, e.g.,
       // an enclosing list item.
       if (handled) {
         event.preventDefault();
         event.stopPropagation();
       }
     },
   };
 
   return {
     AutocompleteList: AutocompleteList
   };
 });