Better CrOS logout button for vertical trays.

ui/gfx/vector_icons_sources.gypi

 # 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.
 
 {
   'variables': {
     'common': [
       'vector_icons/account_box.icon',
       'vector_icons/account_child_invert.icon',
       'vector_icons/account_circle.icon',
@@ skipping 101 matching lines @@
       'vector_icons/radio_button_active.icon',
       'vector_icons/radio_button_normal.icon',
       'vector_icons/remove_box.icon',
       'vector_icons/remove_circle.icon',
       'vector_icons/sad_tab.icon',
       'vector_icons/settings.icon',
       'vector_icons/shelf_applist.1x.icon',
       'vector_icons/shelf_applist.icon',
       'vector_icons/shelf_keyboard.1x.icon',
       'vector_icons/shelf_keyboard.icon',
+      'vector_icons/shelf_logout.1x.icon',
+      'vector_icons/shelf_logout.icon',
       'vector_icons/shelf_notifications.1x.icon',
       'vector_icons/shelf_notifications.icon',
       'vector_icons/shelf_overflow.1x.icon',
       'vector_icons/shelf_overflow.icon',
       'vector_icons/shelf_overview.1x.icon',
       'vector_icons/shelf_overview.icon',
       'vector_icons/smartphone.icon',
       'vector_icons/submenu_arrow.1x.icon',
       'vector_icons/submenu_arrow.icon',
       'vector_icons/subresource_filter_active.icon',
@@ skipping 56 matching lines @@
       'vector_icons/window_control_minimize.icon',
       'vector_icons/window_control_restore.1x.icon',
       'vector_icons/window_control_restore.icon',
       'vector_icons/window_control_right_snapped.1x.icon',
       'vector_icons/window_control_right_snapped.icon',
       'vector_icons/zoom_minus.icon',
       'vector_icons/zoom_plus.icon',
     ],
   },
 }