sync: Refactor update application

sync/engine/apply_updates_command.cc

Index: sync/engine/apply_updates_command.cc
diff --git a/sync/engine/apply_updates_command.cc b/sync/engine/apply_updates_command.cc
index 7d4e72ec9290d063692d741e6a1fd037c1e40b52..639aef7c77fecb6dc5100e93181b126be2891011 100644
--- a/sync/engine/apply_updates_command.cc
+++ b/sync/engine/apply_updates_command.cc
@@ -66,11 +66,10 @@ SyncerError ApplyUpdatesCommand::ModelChangingExecuteImpl(
       &trans, server_type_restriction, &handles);
 
   UpdateApplicator applicator(
-      session->context()->resolver(),
       dir->GetCryptographer(&trans),
-      handles.begin(), handles.end(), session->routing_info(),
+      session->routing_info(),
       session->status_controller().group_restriction());
-  while (applicator.AttemptOneApplication(&trans)) {}
+  applicator.AttemptApplications(&trans, handles);
   applicator.SaveProgressIntoSessionState(
       session->mutable_status_controller()->mutable_conflict_progress(),
       session->mutable_status_controller()->mutable_update_progress());