[Sync] Replace typedef with using.

components/sync/model/sync_data.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_MODEL_SYNC_DATA_H_
 #define COMPONENTS_SYNC_MODEL_SYNC_DATA_H_
 
 #include <stdint.h>
 
 #include <iosfwd>
@@ skipping 92 matching lines @@
 
   // TODO(zea): Query methods for other sync properties: parent, successor, etc.
 
  protected:
   // These data members are protected so derived types like SyncDataLocal and
   // SyncDataRemote can access them.
 
   // Necessary since we forward-declare sync_pb::SyncEntity; see
   // comments in immutable.h.
   struct ImmutableSyncEntityTraits {
-    typedef sync_pb::SyncEntity* Wrapper;
+    using Wrapper = sync_pb::SyncEntity*;
 
     static void InitializeWrapper(Wrapper* wrapper);
 
     static void DestroyWrapper(Wrapper* wrapper);
 
     static const sync_pb::SyncEntity& Unwrap(const Wrapper& wrapper);
 
     static sync_pb::SyncEntity* UnwrapMutable(Wrapper* wrapper);
 
     static void Swap(sync_pb::SyncEntity* t1, sync_pb::SyncEntity* t2);
   };
 
-  typedef Immutable<sync_pb::SyncEntity, ImmutableSyncEntityTraits>
-      ImmutableSyncEntity;
+  using ImmutableSyncEntity =
+      Immutable<sync_pb::SyncEntity, ImmutableSyncEntityTraits>;
 
   // Equal to kInvalidId iff this is local.
   int64_t id_;
 
   // This may be null if the SyncData represents a deleted item.
   base::Time remote_modification_time_;
 
   // The actual shared sync entity being held.
   ImmutableSyncEntity immutable_entity_;
 
@@ skipping 53 matching lines @@
   // requesting the attachments from the network.
   //
   void GetOrDownloadAttachments(
       const AttachmentIdList& attachment_ids,
       const AttachmentService::GetOrDownloadCallback& callback);
 };
 
 // gmock printer helper.
 void PrintTo(const SyncData& sync_data, std::ostream* os);
 
-typedef std::vector<SyncData> SyncDataList;
+using SyncDataList = std::vector<SyncData>;
 
 }  // namespace syncer
 
 #endif  // COMPONENTS_SYNC_MODEL_SYNC_DATA_H_