Use udev for serial device enumeration on Linux

chrome/chrome_tests_unit.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': [
     {
       # This target contains mocks and test utilities that don't belong in
       # production libraries but are used by more than one test executable.
       'target_name': 'test_support_common',
       'type': 'static_library',
@@ skipping 860 matching lines @@
         'browser/extensions/api/messaging/native_message_process_host_unittest.cc',
         'browser/extensions/api/messaging/native_messaging_host_manifest_unittest.cc',
         'browser/extensions/api/messaging/native_messaging_policy_handler_unittest.cc',
         'browser/extensions/api/omnibox/omnibox_unittest.cc',
         'browser/extensions/api/permissions/permissions_api_helpers_unittest.cc',
         'browser/extensions/api/power/power_api_unittest.cc',
         'browser/extensions/api/preference/preference_api_prefs_unittest.cc',
         'browser/extensions/api/proxy/proxy_api_helpers_unittest.cc',
         'browser/extensions/api/push_messaging/obfuscated_gaia_id_fetcher_unittest.cc',
         'browser/extensions/api/push_messaging/push_messaging_invalidation_handler_unittest.cc',
-        'browser/extensions/api/serial/serial_port_enumerator_unittest.cc',
         'browser/extensions/api/signed_in_devices/id_mapping_helper_unittest.cc',
         'browser/extensions/api/signed_in_devices/signed_in_devices_api_unittest.cc',
         'browser/extensions/api/signed_in_devices/signed_in_devices_manager_unittest.cc',
         'browser/extensions/api/socket/socket_api_unittest.cc',
         'browser/extensions/api/socket/tcp_socket_unittest.cc',
         'browser/extensions/api/socket/udp_socket_unittest.cc',
         'browser/extensions/api/sockets_tcp/sockets_tcp_api_unittest.cc',
         'browser/extensions/api/sockets_tcp_server/sockets_tcp_server_api_unittest.cc',
         'browser/extensions/api/sockets_udp/sockets_udp_api_unittest.cc',
         'browser/extensions/api/storage/policy_value_store_unittest.cc',
@@ skipping 2034 matching lines @@
             'browser/ui/app_list/test/fake_profile_store.h',
             'browser/ui/app_list/test/fast_show_pickler_unittest.cc',
             'browser/ui/views/app_list/linux/app_list_linux_unittest.cc',
             'browser/ui/views/app_list/win/app_list_win_unittest.cc',
           ],
         },
       ],
     }],
   ],  # 'conditions'
 }