I think this is what commit 2cf140550635 intended to do since it
specifically mentioned cleaning up the trap in
clutter_x11_texture_pixmap_set_pixmap, but although it moved the untrap
to only be done in the case where Pixmap != None it left the position of
the trap itself unchanged. This meant the error trapping wouldn't be
balanced if pixmap == None since the untrap wouldn't be done. We now
only trap and untrap around the XGetGeometry call done when pixmap !=
None.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2303
bcf20955d3