Firestore listener will get dropped after long period of inactivity or app in background

[elvisun]

I followed a similar design with the ConnectToDataSourceAction action which triggers a listener on login.

https://github.com/brianegan/flutter_architecture_samples/blob/master/firestore_redux/lib/middleware/store_todos_middleware.dart

However I noticed sometimes (haven't been able to reproduce this consistently), after long period of inactivity or app in background, this listener would get cancelled by Firestore. I think we'd need some way to re-subscribe. Have you encountered anything like this?