[MlMt] 6212 update message list jump

[Benjamin Coddington]

Hey Benny et al.

Just updated to 6212, and noticing some new distracting behavior.  As I
delete messages in two-pane view with a hotkey, the message list sometimes
jump-scrolls up or down.  This causes me to have to refocus my reading on
the highlighted message either higher or lower on my screen.

Pretty sure I've not seen this behavior before.  The accustomed behavior is
that as I delete a message, the highlight remains stationary and the /next/
message queue moves up (depending on the sort) into the highlight.

I'm not sure what triggers the jump yet - I am both reading and receiving
mail at the same time (with a very full remote mailbox getting fetchmail'ed
into a local dovecot).

I hope there's a way out (I have to process a /lot/ of mail every day),
maybe I will use the last version for a bit.

Thanks for all the work,
Ben