Rename is_chromeos in chrome/src.

remoting/remoting_locales.gni

 # Copyright 2015 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.
 
 webapp_locale_dir = "$root_gen_dir/remoting/webapp/_locales"
 
 # See also remoting_locales_with_underscores below.
 remoting_locales = [
   "am",
   "ar",
@@ skipping 74 matching lines @@
   "en_GB",
   "es_419",
 
   "fake_bidi",
   "pt_BR",
   "pt_PT",
   "zh_CN",
   "zh_TW",
 ]
 
-if (is_chromeos) {
+if (is_chromeos_ui) {
   remoting_locales += [ "en-US" ]
   remoting_locales_with_underscores += [ "en_US" ]
 }
 
 messages_locales = remoting_locales_with_underscores
-if (!is_chromeos) {
+if (!is_chromeos_ui) {
   # The messages output includes a separate one for en-US that the pak ones
   # don't have. We don't need to do this on ChromeOS since en_US is in the
   # locales list be default there.
   messages_locales += [ "en_US" ]
 }
 
 # The list of .json files generated by remoting_strings.grd.
 remoting_webapp_locale_files =
     process_file_template(
         messages_locales,
         [ "remoting/webapp/_locales/{{source_name_part}}/messages.json" ])