[Sync] Renaming client key to client tag.

components/sync_driver/device_info_service.h

Index: components/sync_driver/device_info_service.h
diff --git a/components/sync_driver/device_info_service.h b/components/sync_driver/device_info_service.h
index fdd649bf57ba2512d3fc015a94d2b6c7ea1a5830..e189d44020d2b1f9411fb825229ee1cffa422757 100644
--- a/components/sync_driver/device_info_service.h
+++ b/components/sync_driver/device_info_service.h
@@ -52,7 +52,7 @@ class DeviceInfoService : public syncer_v2::ModelTypeService,
       scoped_ptr<syncer_v2::MetadataChangeList> metadata_change_list,
       syncer_v2::EntityChangeList entity_changes) override;
   void LoadMetadata(MetadataCallback callback) override;
-  void GetData(ClientKeyList client_keys, DataCallback callback) override;
+  void GetData(ClientTagList client_tags, DataCallback callback) override;
   void GetAllData(DataCallback callback) override;
   std::string GetClientTag(const syncer_v2::EntityData& entity_data) override;