Pass error messages from native messaging to web-app.

remoting/webapp/files.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.
 
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@@ skipping 262 matching lines @@
 remoting_webapp_js_host_control_files = [
   "crd/js/buffered_signal_strategy.js",
   "crd/js/host_controller.js",
   "crd/js/host_daemon_facade.js",
   "crd/js/host_screen.js",
   "crd/js/host_session.js",
   "crd/js/host_setup_dialog.js",
   "crd/js/host_install_dialog.js",
   "crd/js/host_installer.js",
   "crd/js/it2me_host_facade.js",
+  "crd/js/native_message_host_log_message_handler.js",
   "crd/js/paired_client_manager.js",
 ]
 
 # Files for displaying (in the client) info about available hosts.
 remoting_webapp_js_host_display_files = [
   "crd/js/host_list.js",
   "crd/js/host_list_api.js",
   "crd/js/host_table_entry.js",
   "crd/js/local_host_section.js",
 
@@ skipping 374 matching lines @@
       ar_main_template,
       ar_feedback_consent_template,
       ar_loading_window_template,
       remoting_webapp_template_message_window,
       remoting_webapp_template_wcs_sandbox,
     ] + ar_main_template_files + ar_all_js_files
 
 webapp_js_files = remoting_webapp_unittest_html_all_js_files +
                   remoting_webapp_wcs_sandbox_html_js_files +
                   remoting_webapp_background_html_js_files