persist method
Persist function called with the bath of documents that have changed (including been deleted) within the last throttle window
specified by the Persistor.persistenceThrottle
duration.
Implementation
@override
persist(docs) async {
// Marshall file persist documents to be sent to and persisted by the worker isolate.
final data = docs.map((doc) => doc.toPersistenceDoc()).toList();
await _sendMessage(PersistMessageRequest(data: data));
}