[Clean-up] Remove some dead code for handling Webstore sign-in.

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.
 {
   'variables': {
     'chrome_unit_tests_sources': [
       '../apps/app_shim/app_shim_host_mac_unittest.cc',
       '../apps/app_shim/extension_app_shim_handler_mac_unittest.cc',
       '../apps/saved_devices_service_unittest.cc',
       '../apps/saved_files_service_unittest.cc',
@@ skipping 702 matching lines @@
       'browser/shell_integration_linux_unittest.cc',
       'browser/shell_integration_win_unittest.cc',
       'browser/signin/account_reconcilor_unittest.cc',
       'browser/signin/account_service_flag_fetcher_unittest.cc',
       'browser/signin/easy_unlock_screenlock_state_handler_unittest.cc',
       'browser/signin/local_auth_unittest.cc',
       'browser/signin/signin_error_notifier_ash_unittest.cc',
       'browser/signin/signin_global_error_unittest.cc',
       'browser/signin/signin_manager_unittest.cc',
       'browser/signin/signin_names_io_thread_unittest.cc',
-      'browser/signin/signin_promo_unittest.cc',
       'browser/signin/signin_tracker_unittest.cc',
       'browser/signin/test_signin_client_builder.cc',
       'browser/speech/extension_api/extension_manifests_tts_unittest.cc',
       'browser/speech/tts_controller_unittest.cc',
       'browser/spellchecker/feedback_sender_unittest.cc',
       'browser/spellchecker/feedback_unittest.cc',
       'browser/spellchecker/misspelling_unittest.cc',
       'browser/spellchecker/spellcheck_action_unittest.cc',
       'browser/spellchecker/spellcheck_custom_dictionary_unittest.cc',
       'browser/spellchecker/spellcheck_host_metrics_unittest.cc',
@@ skipping 2137 matching lines @@
               'dependencies': [
                 '../tools/xdisplaycheck/xdisplaycheck.gyp:xdisplaycheck',
               ],
             }],
           ],
         },
       ],
     }],
   ],  # 'conditions'
 }