[Sync] Remove backend unrecoverable error handler

sync/internal_api/sync_backup_manager.cc

Index: sync/internal_api/sync_backup_manager.cc
diff --git a/sync/internal_api/sync_backup_manager.cc b/sync/internal_api/sync_backup_manager.cc
index 4d06b988d45a6b55e6d697a5bde75a285a9d1f6b..147da320b27458a38f62dcf09b9abd28e5ece70f 100644
--- a/sync/internal_api/sync_backup_manager.cc
+++ b/sync/internal_api/sync_backup_manager.cc
@@ -24,7 +24,7 @@ void SyncBackupManager::Init(InitArgs* args) {
           args->database_location,
           args->internal_components_factory.get(),
           InternalComponentsFactory::STORAGE_ON_DISK_DEFERRED,
-          args->unrecoverable_error_handler.Pass(),
+          args->unrecoverable_error_handler,
           args->report_unrecoverable_error_function)) {
     GetUserShare()->directory->CollectMetaHandleCounts(
         &status_.num_entries_by_type, &status_.num_to_delete_entries_by_type);