Feeds event with relation to unknown to the widget

[maheichyk]

Events that relate to unknown parent are not added to the timeline and therefore are not passed to the widget. Room timeline is used in StopGapWidget to check if event is before the marker in order to pass it.

This PR suggests to ignore marker timeline logic for these events.

Checklist

• Tests written for new code (and old code if feasible)
• Linter and other CI checks pass
• Sign-off given on the changes (see CONTRIBUTING.md)

Type: defect

[dbkr]

I think this seems reasonable, although maybe we should default to sending the event on if we can't find either the event or the receipt, rather than special-casing events whose parent we can't find? (ie. rename isBeforeMark to shouldForward or something, set it to true to start with and set it to false in the first clause rather than the second... and comment it, obviously).

[maheichyk]

I have changed isBeforeMark to shouldForward that makes easier to understand this logic, but I can’t follow on the suggestion to change:

although maybe we should default to sending the event on if we can't find either the event or the receipt, rather than special-casing events whose parent we can't find

It not looks clear to me how event or the receipt find could resolve the same issue. Could you please explain more exactly what you mean with that?

[maheichyk]

@dbkr could you please have a look on the changes?

[dbkr]

Okay, I was just suggesting that, since the problem here is that we can't prove that the event is after the read marker because we can't find the event, we could also just default to forwarding if we can't prove the event hasn't been read, which I think would probably be safe enough. That said, this is a smaller change, so it seems fine.