getting rid of the "Oh no!" window when restarting gnome-shell

[Tim Cuthbertson <tim gfxmonk net>]

In hacking on gnome-shell, I often break things and have to restart
the shell (or crash it).

It seems that gnome-session notices this, as after gnome-shell exits a
few times (because I broke or restarted it), gnome-session pops up a
fullscreen X window saying something along the lines of "Oh no,
something is broken, you'll need to log out and back in again".

I really don't want to lose my session every time this happens, and I
know that gnome-shell starts up again just fine, but the gnome-session
window obscures it completely. I googled around but couldn't find any
way of telling gnome-session that everything's fine.

I ended up installing python-wnck, and doing something along the lines of:
import wnck
wins = wnck.screen_get_default().get_windows()
< take a while to figure out which window belongs to gnome-session >
wins[12].close(0)

But that was difficult, and seems a crazy thing to have to do as part
of regular development. Am I missing something? Do others get the same
error message, and how do you get rid of it without logging out and
back in again?

Cheers,
 - Tim.