We correctly allowed using the MSC2716 batch endpoint for
the room creator in existing room versions but accidentally didn't track
the events because of a logic flaw.
This prevented you from connecting subsequent chunks together because it would
throw the unknown batch ID error.
We only want to process MSC2716 events when:
- The room version supports MSC2716
- Any room where the homeserver has the `msc2716_enabled` experimental feature enabled and the event is from the room creator
Eric Eastwood