[SyncFS] Use pointers to MetadataDatabaseIndexInterface

chrome/chrome_browser.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': [
     {
       'target_name': 'browser',
       'type': 'static_library',
       'variables': { 'enable_wexit_time_destructors': 1, },
@@ skipping 2335 matching lines @@
         'browser/sync_file_system/drive_backend/folder_creator.cc',
         'browser/sync_file_system/drive_backend/folder_creator.h',
         'browser/sync_file_system/drive_backend/list_changes_task.cc',
         'browser/sync_file_system/drive_backend/list_changes_task.h',
         'browser/sync_file_system/drive_backend/local_to_remote_syncer.cc',
         'browser/sync_file_system/drive_backend/local_to_remote_syncer.h',
         'browser/sync_file_system/drive_backend/metadata_database.cc',
         'browser/sync_file_system/drive_backend/metadata_database.h',
         'browser/sync_file_system/drive_backend/metadata_database_index.cc',
         'browser/sync_file_system/drive_backend/metadata_database_index.h',
+        'browser/sync_file_system/drive_backend/metadata_database_index_interface.h',
         'browser/sync_file_system/drive_backend/metadata_db_migration_util.cc',
         'browser/sync_file_system/drive_backend/metadata_db_migration_util.h',
         'browser/sync_file_system/drive_backend/register_app_task.cc',
         'browser/sync_file_system/drive_backend/register_app_task.h',
         'browser/sync_file_system/drive_backend/remote_change_processor_on_worker.cc',
         'browser/sync_file_system/drive_backend/remote_change_processor_on_worker.h',
         'browser/sync_file_system/drive_backend/remote_change_processor_wrapper.cc',
         'browser/sync_file_system/drive_backend/remote_change_processor_wrapper.h',
         'browser/sync_file_system/drive_backend/remote_to_local_syncer.cc',
         'browser/sync_file_system/drive_backend/remote_to_local_syncer.h',
@@ skipping 1424 matching lines @@
             'package_name': 'org/chromium/chrome/browser',
             'template_deps': ['browser/android/tab_load_status.h'],
           },
           'includes': [ '../build/android/java_cpp_template.gypi' ],
         },
       ],
      },
     ],
   ],
 }