[Sync] Replace typedef with using.

components/sync/engine_impl/process_updates_util.h

 // 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.
 
 #ifndef COMPONENTS_SYNC_ENGINE_IMPL_PROCESS_UPDATES_UTIL_H_
 #define COMPONENTS_SYNC_ENGINE_IMPL_PROCESS_UPDATES_UTIL_H_
 
 #include <stdint.h>
 
 #include <vector>
 
 #include "components/sync/base/model_type.h"
 
 namespace sync_pb {
 class SyncEntity;
 }
 
 namespace syncer {
 
 class StatusController;
 struct UpdateCounters;
 
 namespace syncable {
 class ModelNeutralWriteTransaction;
 class Directory;
 }
 
-typedef std::vector<const sync_pb::SyncEntity*> SyncEntityList;
+using SyncEntityList = std::vector<const sync_pb::SyncEntity*>;
 
 // Processes all the updates associated with a single ModelType.
 void ProcessDownloadedUpdates(syncable::Directory* dir,
                               syncable::ModelNeutralWriteTransaction* trans,
                               ModelType type,
                               const SyncEntityList& applicable_updates,
                               StatusController* status,
                               UpdateCounters* counters);
 
 // Tombstones all entries of |type| whose versions are older than
 // |version_watermark| unless they are type root or unsynced/unapplied.
 void ExpireEntriesByVersion(syncable::Directory* dir,
                             syncable::ModelNeutralWriteTransaction* trans,
                             ModelType type,
                             int64_t version_watermark);
 
 }  // namespace syncer
 
 #endif  // COMPONENTS_SYNC_ENGINE_IMPL_PROCESS_UPDATES_UTIL_H_