[Sync] Fixing easy lint violations.

components/sync/core_impl/sync_manager_impl.h

 // 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.
 
 #ifndef COMPONENTS_SYNC_CORE_IMPL_SYNC_MANAGER_IMPL_H_
 #define COMPONENTS_SYNC_CORE_IMPL_SYNC_MANAGER_IMPL_H_
 
 #include <stdint.h>
 
 #include <map>
+#include <memory>
 #include <string>
 #include <vector>
 
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "components/sync/base/cryptographer.h"
 #include "components/sync/base/time.h"
 #include "components/sync/core/sync_manager.h"
 #include "components/sync/core/user_share.h"
 #include "components/sync/core_impl/change_reorder_buffer.h"
@@ skipping 312 matching lines @@
   std::unique_ptr<SyncEncryptionHandlerImpl> sync_encryption_handler_;
 
   base::WeakPtrFactory<SyncManagerImpl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(SyncManagerImpl);
 };
 
 }  // namespace syncer
 
 #endif  // COMPONENTS_SYNC_CORE_IMPL_SYNC_MANAGER_IMPL_H_