writeToPersistentStorage method Null safety

Future<void> writeToPersistentStorage()


Future<void> writeToPersistentStorage() async {
  // We could query needsSave here, but this is called infrequently.
  // A full audit to make sure needsSave is always updated would be needed
  // to restore the query here.
  needsSave = false;
  final storage = await SharedPreferences.getInstance();
  String js = json.encode(toJson());
  await storage.setString(_persistentStorageKey, js);