More consistent handling of out-of-order messages

[fjarri]

Suppose a protocol has a round A that can transition either to round B or round C. If Node 1 is in round A, and receives a message for round B (from another node who's already in it), but later transitions to round C, the message is discarded with no repercussions. But if Node 1 is already in round C, the message is treated as an unprovable malicious action and the event is recorded.

For consistency, these situations should be treated the same. Ideally, both events should not be recorded. To do that, when transitioning to round C we need to somehow pass on the information that another possible round other nodes can be in is round B, so we shouldn't treat messages from it as malicious actions.