[Sync] Move SyncPrefs into sync_driver component

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 1324 matching lines @@
         'browser/sync/profile_sync_service_startup_unittest.cc',
         'browser/sync/profile_sync_service_typed_url_unittest.cc',
         'browser/sync/profile_sync_service_unittest.cc',
         'browser/sync/profile_sync_test_util.cc',
         'browser/sync/profile_sync_test_util.h',
         'browser/sync/sessions2/sessions_sync_manager_unittest.cc',
         'browser/sync/sessions2/tab_node_pool2_unittest.cc',
         'browser/sync/startup_controller_unittest.cc',
         'browser/sync/sync_global_error_unittest.cc',
         'browser/sync/sync_policy_handler_unittest.cc',
-        'browser/sync/sync_prefs_unittest.cc',
         'browser/sync/sync_startup_tracker_unittest.cc',
         'browser/sync/sync_ui_util_unittest.cc',
         'browser/sync/test/test_http_bridge_factory.cc',
         'browser/sync/test/test_http_bridge_factory.h',
         'browser/sync/test_profile_sync_service.cc',
         'browser/sync/test_profile_sync_service.h',
         'browser/sync_file_system/drive_backend/conflict_resolver_unittest.cc',
         'browser/sync_file_system/drive_backend/drive_backend_sync_unittest.cc',
         'browser/sync_file_system/drive_backend/drive_backend_test_util.cc',
         'browser/sync_file_system/drive_backend/drive_backend_test_util.h',
@@ skipping 1538 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'
 }