[Tails-testers] Gnome shell crashes and *does not* restart (…

This report may be similar to Bug #11188 but I can't tell due to a lack
of being able to control the system enough to get information.

I had Gnome terminal open with several tabs, along with a browswer
window and one other application. Gnome shell crashed when switching
the browser window into focus. The Gnome menus were then gone, as were
decorations on windows. I could still get the browser window to scroll.
Ctrl-Alt-F2 to try to get to a text console had no effect. Alt-Tab to
switch tasks had no effect. I could clock on and move the Gnome
terminal around, but could not get any of the terminals themselves into
focus, so could not type in them. I could close any of the terminal
tabs by clicking, start a new one, or open a new terminal window by
right-clicking on the Desktop, but under all circumstances the cursor at
the terminal remained an "empty rectangle" (i.e. not in focus) such that
I couldn't type in the terminal.

This seems like a rather tricky thing to debug because in this state the
system doesn't have enough functionality to allow me to get information.
Normally I'd want to ssh into the system from outside to be able to
read logs, but since this is a security distribution, naturally I didn't
enable that beforehand to allow doing so.

I'd appreciate hints as to what I might try in this situation to debug
this, in case I'm able to duplicate it. (It happened on the first time
I tried 3.0~alpha1 and I'm assuming it's not only going to be "beginners
luck". :-P)

-- krait