Implement fetching, caching and retrieval of external policy data

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 997 matching lines @@
         'browser/password_manager/password_store_default_unittest.cc',
         'browser/password_manager/password_store_mac_unittest.cc',
         'browser/password_manager/password_store_win_unittest.cc',
         'browser/password_manager/password_store_x_unittest.cc',
         'browser/performance_monitor/database_unittest.cc',
         'browser/plugins/plugin_finder_unittest.cc',
         'browser/plugins/plugin_metadata_unittest.cc',
         'browser/plugins/plugin_prefs_unittest.cc',
         'browser/policy/async_policy_provider_unittest.cc',
         'browser/policy/browser_policy_connector_unittest.cc',
+        'browser/policy/cloud/cloud_external_data_manager_base_unittest.cc',
         'browser/policy/cloud/cloud_external_data_store_unittest.cc',
         'browser/policy/cloud/cloud_policy_client_unittest.cc',
         'browser/policy/cloud/cloud_policy_core_unittest.cc',
         'browser/policy/cloud/cloud_policy_manager_unittest.cc',
         'browser/policy/cloud/cloud_policy_refresh_scheduler_unittest.cc',
         'browser/policy/cloud/cloud_policy_service_unittest.cc',
         'browser/policy/cloud/cloud_policy_validator_unittest.cc',
         'browser/policy/cloud/component_cloud_policy_service_unittest.cc',
         'browser/policy/cloud/component_cloud_policy_store_unittest.cc',
         'browser/policy/cloud/component_cloud_policy_updater_unittest.cc',
@@ skipping 1628 matching lines @@
               # more details.
               'DebugInformationFormat': '3',
               'ProgramDataBaseFileName': '<(PRODUCT_DIR)/unit_tests.exe.pdb',
             },
           },
         },
       ],
     }],
   ],  # 'conditions'
 }