Moves shared history test helpers into util classes.

components/history.gypi

 # Copyright 2014 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': [
     {
       # GN version: //components/history/core/browser
       'target_name': 'history_core_browser',
       'type': 'static_library',
@@ skipping 170 matching lines @@
         # Note: sources list duplicated in GN build.
         'history/core/test/database_test_utils.cc',
         'history/core/test/database_test_utils.h',
         'history/core/test/fake_web_history_service.cc',
         'history/core/test/fake_web_history_service.h',
         'history/core/test/history_backend_db_base_test.cc',
         'history/core/test/history_backend_db_base_test.h',
         'history/core/test/history_client_fake_bookmarks.cc',
         'history/core/test/history_client_fake_bookmarks.h',
         'history/core/test/history_unittest_base.cc',
+        'history/core/test/history_service_test_util.cc',
+        'history/core/test/history_service_test_util.h',
         'history/core/test/history_unittest_base.h',
         'history/core/test/test_history_database.cc',
         'history/core/test/test_history_database.h',
         'history/core/test/thumbnail-inl.h',
         'history/core/test/thumbnail.cc',
         'history/core/test/thumbnail.h',
         'history/core/test/thumbnail_ios.mm',
         'history/core/test/wait_top_sites_loaded_observer.cc',
         'history/core/test/wait_top_sites_loaded_observer.h',
       ],
@@ skipping 57 matching lines @@
             'history/ios/browser/history_database_helper.cc',
             'history/ios/browser/history_database_helper.h',
             'history/ios/browser/web_state_top_sites_observer.cc',
             'history/ios/browser/web_state_top_sites_observer.h',
           ],
         },
       ],
     }],
   ],
 }