[android] getCameraPose() returns null value every time

[anshgandhi4]

This seems to be an issue on Android only, but all calls to getCameraPose() result in a null return value with the following error message.

Error caught: type '_Map<Object?, Object?>' is not a subtype of type 'List<dynamic>?' in type cast

The error seems to be printed from this line in ar_session_manager.dart.