Set wallpaper from right click menu in Files app.

ui/file_manager/file_manager/foreground/js/compiled_resources.gyp

 # Copyright 2014 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.
 {
   'targets': [
     {
       'target_name': 'main',
       'variables': {
         'depends': [
           '<@(cws_widget_container)',
@@ skipping 138 matching lines @@
           './metadata/byte_reader.js',
         ],
         'externs': [
           '<(EXTERNS_DIR)/chrome_extensions.js',
           '<(EXTERNS_DIR)/chrome_send.js',
           '<(EXTERNS_DIR)/command_line_private.js',
           '<(EXTERNS_DIR)/file_manager_private.js',
           '<(EXTERNS_DIR)/metrics_private.js',
           '../../../../../third_party/analytics/externs.js',
           '../../../externs/chrome_echo_private.js',
+          '../../../externs/chrome_wallpaper.js',
           '../../../externs/chrome_webstore_widget_private.js',
           '../../../externs/chrome_test.js',
           '../../../externs/connection.js',
           '../../../externs/css_rule.js',
           '../../../externs/es6_workaround.js',
           '../../../externs/html_menu_item_element.js',
           '../../../externs/launcher_search_provider.js',
           '../../../externs/webview_tag.js',
           '../../../externs/paper_elements.js',
           '../../../externs/platform.js',
           '../../common/js/externs.js',
         ],
       },
       'includes': [
         '../../../../../components/chrome_apps/webstore_widget/cws_widget/compiled_resources.gypi',
         '../../../compile_js.gypi',
       ],
     }
   ],
 }