When a window manager does --replace to replace a running metacity instance, that instance doesn't shutdown properly.

It's supposed to set its restart hint to SmRestartIfRunning so the session manager doesn't immediately try to restart it when it exits.

It used to do this, but looks like it got broken by this commit:

http://git.gnome.org/cgit/metacity/commit/?id=abbd057eb967e6ab462ffe305f41b2b04d417b25

process_selection_clear sets the_display to NULL so meta_session_shutdown aborts early.

Note the session manager talks over libICE not through the X server so you don't need a display to talk to the session manager.

I don't think it makes sense to call

warn_about_lame_clients_and_finish_interact 

from meta_session_shutdown either.  On shutdown the session manager treats the window manager special.  After all other apps have chimed in, the session managers asks for phase 2 of the shutdown process, when put in that phase, it will do an interaction request.  if the session manager grants that request, then 

interact_callback

will get called which calls

warn_about_lame_clients_and_finish_interact 

while there is still a display active.

Note, we'd never want to call that function when being --replaced.  

I think I'd recommend reverting the commit entirely. Did it solve a specific problem?