We were only calling xwl_present_unrealize_window for the toplevel
window, but the list can contain entries from child windows as well,
in which case we were leaving dangling pointers to freed memory.
Closes: https://gitlab.freedesktop.org/xorg/xserver/issues/1000
Fixes: c5067feaee "xwayland: Use single frame callback for Present
flips and normal updates"
Reviewed-by: Olivier Fourdan <ofourdan@redhat.com>
Tested-by: Olivier Fourdan <ofourdan@redhat.com>
(cherry picked from commit 5e91587302)
b259485975