Implements the storage free space watching functionality into storage info provider

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 675 matching lines @@
         'browser/extensions/api/omnibox/omnibox_unittest.cc',
         'browser/extensions/api/permissions/permissions_api_helpers_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/socket/socket_api_unittest.cc',
         'browser/extensions/api/socket/tcp_socket_unittest.cc',
         'browser/extensions/api/socket/udp_socket_unittest.cc',
         'browser/extensions/api/system_info_storage/storage_info_provider_linux_unittest.cc',
+        'browser/extensions/api/system_info_storage/storage_info_provider_unittest.cc',
         'browser/extensions/api/web_navigation/frame_navigation_state_unittest.cc',
         'browser/extensions/api/web_request/form_data_parser_unittest.cc',
         'browser/extensions/api/web_request/upload_data_presenter_unittest.cc',
         'browser/extensions/api/web_request/web_request_api_unittest.cc',
         'browser/extensions/api/web_request/web_request_permissions_unittest.cc',
         'browser/extensions/api/web_request/web_request_time_tracker_unittest.cc',
         'browser/extensions/app_notification_manager_sync_unittest.cc',
         'browser/extensions/app_notification_manager_unittest.cc',
         'browser/extensions/app_notification_storage_unittest.cc',
         'browser/extensions/app_notification_test_util.cc',
@@ skipping 1585 matching lines @@
             'unit_tests.isolate',
           ],
           'sources': [
             'unit_tests.isolate',
           ],
         },
       ],
     }],
   ],  # 'conditions'
 }