This was always used with 'consoleplayer' which really is the only thing making sense here. But this is a part of the global state which should be avoided in play code.
In particular, this makes no real sense in case of secondary maps where it should always return false.
- offloaded key list generation for alternative HUD to non-UI parts.
This change also revealed a problem with handling empty sprites in the key list so this got fixed, too.
- replaced Key.KeyNumber with special1. This is only for internal bookkeeping purposes so there's really no need to complicate this with a new variable when this one works just as well.
