docs: @Override
    public int onStartCommand(final Intent intent, int flags, final int startId) {
      Timber.v("onStartCommand called.");
      if (intent != null) {
        final OfflineDownloadOptions offlineDownload = intent.getParcelableExtra(KEY_BUNDLE);
        if (offlineDownload != null) {
          onResolveCommand(intent.getAction(), offlineDownload);
        } else {
          stopSelf(startId);
          throw new NullPointerException("A DownloadOptions instance must be passed into the service to"
              + " begin downloading.");
        }
      }
      return START_STICKY;
    }