trackStart method Null safety

Implementation

static Future<bool> trackStart(
    LocalDatabase localDatabase, BuildContext context) async {
  final TrackingDatabaseHelper trackingDatabaseHelper =
      TrackingDatabaseHelper(localDatabase);
  final Size size = MediaQuery.of(context).size;
  final Map<String, String> data = <String, String>{};

  // The current count of visits for this visitor
  data.addIfVAndNew(
    '_idvc',
    trackingDatabaseHelper.getAppVisits().toString(),
  );
  // The UNIX timestamp of this visitor's previous visit
  data.addIfVAndNew(
    '_viewts',
    trackingDatabaseHelper.getPreviousVisitUnix().toString(),
  );
  // The UNIX timestamp of this visitor's first visit
  data.addIfVAndNew(
    '_idts',
    trackingDatabaseHelper.getFirstVisitUnix().toString(),
  );
  // Device resolution
  data.addIfVAndNew('res', '${size.width}x${size.height}');
  data.addIfVAndNew('lang', Localizations.localeOf(context).languageCode);
  data.addIfVAndNew('country', Localizations.localeOf(context).countryCode);

  return _track(
    _initAction,
    data,
  );
}