[Sync] Replace typedef with using.

components/sync/driver/shared_change_processor.h

Index: components/sync/driver/shared_change_processor.h
diff --git a/components/sync/driver/shared_change_processor.h b/components/sync/driver/shared_change_processor.h
index 4b8aa9681bd61bd6aa526dde85282a84b647376b..280ad5e2be112469e285fa5292498e6323535c76 100644
--- a/components/sync/driver/shared_change_processor.h
+++ b/components/sync/driver/shared_change_processor.h
@@ -53,10 +53,10 @@ struct UserShare;
 class SharedChangeProcessor
     : public base::RefCountedThreadSafe<SharedChangeProcessor> {
  public:
-  typedef base::Callback<void(DataTypeController::ConfigureResult start_result,
-                              const SyncMergeResult& local_merge_result,
-                              const SyncMergeResult& syncer_merge_result)>
-      StartDoneCallback;
+  using StartDoneCallback =
+      base::Callback<void(DataTypeController::ConfigureResult start_result,
+                          const SyncMergeResult& local_merge_result,
+                          const SyncMergeResult& syncer_merge_result)>;
 
   // Create an uninitialized SharedChangeProcessor.
   explicit SharedChangeProcessor(ModelType type);