gyp: don't build gamepad_platform_data_fetcher_linux.cc when udev is disabled

device/gamepad/gamepad.gyp

 # 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': {
     'chromium_code': 1,
   },
   'targets': [
     {
@@ skipping 36 matching lines @@
         'xbox_data_fetcher_mac.cc',
         'xbox_data_fetcher_mac.h',
       ],
       'conditions': [
         ['OS=="win"', {
           'msvs_disabled_warnings': [4267, ],
         }],
         ['OS!="win" and OS!="mac" and OS!="android" and (OS!="linux" or use_udev==0)', {
           'sources': [
             'gamepad_platform_data_fetcher.cc',
-          ]
+          ],
+          'sources!': [
+            'gamepad_platform_data_fetcher_linux.cc',
+          ],
         }],
       ],
     },
     {
       # GN version: //device/gamepad:test_helpers
       'target_name': 'device_gamepad_test_helpers',
       'type': 'static_library',
       'dependencies': [
         '../../base/base.gyp:base',
         'device_gamepad',
       ],
       'sources': [
         # Note: file list duplicated in GN build.
         'gamepad_test_helpers.cc',
         'gamepad_test_helpers.h',
       ],
     },
   ],
 }