ChromeOS: Implement MediaTransferProtocolManager observer.

chrome/chrome_tests.gypi

 # Copyright (c) 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.
 {
   'variables' : {
     'pyautolib_sources': [
       'app/chrome_command_ids.h',
       'app/chrome_dll_resource.h',
       'common/automation_constants.h',
       'common/pref_names.cc',
@@ skipping 1141 matching lines @@
         'browser/chromeos/kiosk_mode/kiosk_mode_idle_logout_unittest.cc',
         'browser/chromeos/kiosk_mode/kiosk_mode_screensaver_unittest.cc',
         'browser/chromeos/kiosk_mode/kiosk_mode_settings_unittest.cc',
         'browser/chromeos/language_preferences_unittest.cc',
         'browser/chromeos/login/mock_auth_attempt_state_resolver.cc',
         'browser/chromeos/login/mock_auth_attempt_state_resolver.h',
         'browser/chromeos/login/online_attempt_unittest.cc',
         'browser/chromeos/login/parallel_authenticator_unittest.cc',
         'browser/chromeos/login/user_manager_unittest.cc',
         'browser/chromeos/mobile_config_unittest.cc',
+        'browser/chromeos/mtp/media_transfer_protocol_device_observer_unittest.cc',
         'browser/chromeos/network_message_observer_unittest.cc',
         'browser/chromeos/offline/offline_load_page_unittest.cc',
         'browser/chromeos/oom_priority_manager_unittest.cc',
         'browser/chromeos/preferences_unittest.cc',
         'browser/chromeos/process_proxy/process_output_watcher_unittest.cc',
         'browser/chromeos/proxy_config_service_impl_unittest.cc',
         'browser/chromeos/settings/cros_settings_unittest.cc',
         'browser/chromeos/settings/device_settings_provider_unittest.cc',
         'browser/chromeos/settings/mock_owner_key_utils.cc',
         'browser/chromeos/settings/mock_owner_key_utils.h',
@@ skipping 3558 matching lines @@
                 '--result', '<@(_outputs)',
                 '--isolate', 'browser_tests.isolate',
               ],
             },
           ],
         },
       ],
     }],
   ],  # 'conditions'
 }