code: public static void requestSyncNow(Account account, String authority, @Nullable Bundle extras) {
          if (extras == null) {
              extras = new Bundle();
          }
          extras.putBoolean(SYNC_EXTRAS_MANUAL, true);
          extras.putBoolean(SYNC_EXTRAS_EXPEDITED, true);
          ContentResolver.requestSync(account, authority, extras);
      }
docs: Request that a sync starts immediately.
  
  @see ContentResolver#requestSync(Account, String, Bundle)