Fixed gear menu navigation using keyboard.

chrome/browser/resources/file_manager/css/file_manager.css

 /* 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. */
 
 html {
   height: 100%;
 }
 
 html.col-resize * {
   cursor: col-resize !important;
@@ skipping 1454 matching lines @@
 body[type='full-page'] [invisibleif~='full-page'],
 
 body[type='folder'] [visibleif]:not([visibleif~='folder']),
 body[type='saveas-file'] [visibleif]:not([visibleif~='saveas-file']),
 body[type='open-file'] [visibleif]:not([visibleif~='open-file']),
 body[type='open-multi-file'] [visibleif]:not([visibleif~='open-multi-file']),
 body[type='full-page'] [visibleif]:not([visibleif~='full-page']) {
   display: none;
 }
 
-body:not([ctrl-pressing]) [required_attr='ctrl-pressing'] {
-  display: none;
-}
-
-body:not([drive]) [required_drive] {
-  display: none;
-}
-
 #gear-button::before {
   background-image: url('../images/files/ui/settings.svg');
   background-position: 20px center;
   background-repeat: no-repeat;
   bottom: 0;
   content: '';
   left: 0;
   opacity: 0.75;
   position: absolute;
   right: 0;
@@ skipping 212 matching lines @@
 }
 
 list.autocomplete-suggestions[hasElementFocus] > [selected],
 list.autocomplete-suggestions[hasElementFocus] > [lead],
 list.autocomplete-suggestions:not([hasElementFocus]) > [selected],
 list.autocomplete-suggestions:not([hasElementFocus]) > [lead] {
   background-color: rgb(238, 238, 238);
   background-image: none;
   border: 1px solid white;
 }