[Sync] Removing duplicated includes between cc and h files.

components/sync/driver/glue/sync_backend_host_impl.cc

 // Copyright 2013 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.
 
 #include "components/sync/driver/glue/sync_backend_host_impl.h"
 
-#include <map>
 #include <utility>
-#include <vector>
 
 #include "base/command_line.h"
 #include "base/feature_list.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "components/invalidation/public/invalidation_service.h"
 #include "components/invalidation/public/object_id_invalidation_map.h"
 #include "components/signin/core/browser/signin_client.h"
 #include "components/sync/base/experiments.h"
 #include "components/sync/core/activation_context.h"
 #include "components/sync/core/base_transaction.h"
 #include "components/sync/core/http_bridge.h"
 #include "components/sync/core/internal_components_factory.h"
 #include "components/sync/core/internal_components_factory_impl.h"
-#include "components/sync/core/sync_manager.h"
 #include "components/sync/core/sync_manager_factory.h"
 #include "components/sync/driver/glue/sync_backend_host_core.h"
 #include "components/sync/driver/glue/sync_backend_registrar.h"
 #include "components/sync/driver/invalidation_helper.h"
 #include "components/sync/driver/sync_client.h"
 #include "components/sync/driver/sync_driver_switches.h"
 #include "components/sync/driver/sync_frontend.h"
 #include "components/sync/driver/sync_prefs.h"
 #include "components/sync/engine/events/protocol_event.h"
 #include "components/sync/engine/sync_string_conversions.h"
@@ skipping 803 matching lines @@
     const syncer::SyncManager::ClearServerDataCallback& frontend_callback) {
   DCHECK(ui_thread_->BelongsToCurrentThread());
   frontend_callback.Run();
 }
 
 }  // namespace browser_sync
 
 #undef SDVLOG
 
 #undef SLOG