Enable devices page UI on MacOSX

chrome/chrome_browser_ui.gypi

 # Copyright 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.
 
 {
   'targets': [
     {
       'target_name': 'browser_ui',
       'type': 'static_library',
       'variables': { 'enable_wexit_time_destructors': 1, },
@@ skipping 3401 matching lines @@
             'browser/ui/webui/options/geolocation_options_handler.cc',
             'browser/ui/webui/options/geolocation_options_handler.h',
           ],
         }],
         ['enable_webrtc==0', {
           'sources!': [
             'browser/ui/webui/media/webrtc_logs_ui.cc',
             'browser/ui/webui/media/webrtc_logs_ui.h',
           ],
         }],
-        ['enable_mdns==1', {
+        ['enable_service_discovery==1', {
           'sources': [
             'browser/ui/webui/local_discovery/local_discovery_ui.cc',
             'browser/ui/webui/local_discovery/local_discovery_ui.h',
             'browser/ui/webui/local_discovery/local_discovery_ui_handler.cc',
             'browser/ui/webui/local_discovery/local_discovery_ui_handler.h',
           ],
         }],
       ],
     },
   ],
 }