[Evolution] Can't collapse folder tree

[Kenneth Porter <shiva sewingwitch com>]

I've seen this in the distant past but not recently. Using the 9/23
snapshot, I'm trying to collapse one of my folder trees and it pops
right back open again. It was working fine earlier in the session. The
folder in question is a subfolder of the top-level namespace folder of
an IMAP connection (shiva sewingwitch com/mail/foo), but in the past
I've seen this with the local folders tree. Clicking on the '-' at any
level of the tree above the problem folder causes the tree to collapse
and immediately re-expand.