wild popup bug

[Edscott Wilson <edscott wilson garcia gmail com>]

This is a follow up on
http://comments.gmane.org/gmane.comp.gnome.lib.gtk%2B.devel.apps/31337

I've kept investigating the bug and found that it occurs on any processor,
but only when fvwm2 is the WM and the desktop is located beyond the fourth
desktop. It does not occur in gtk-2.24, but invariable occurs in GTK+3.4.2
and again in GTK+3.8.0. I'm now quite convinced it is a gtk bug and will
try to cook up a simple example to reproduce at will before filing a bug
report.

Apparently the problem arises from a race with fvwm on accessing XServer
information regarding the root window geometry in order to place the popup
menu. The bug also happens, in the exact same manner, when placing the
tooltip window.