Lots of code calls gtk_menu_popup() and we don't want to resize the
window needlessly.
In this particular case, keyboard navigation to submenus caused those
submenus to shrink.
Note: I'm not sure this fix doesn't have nasty side effects, as I'm not
a specialist on menu popup code, so if it does, we'll need to revert it.
Until then, let's keep it, it fixes a bug.
/* Compute the size of the toplevel and realize it so we
* can scroll correctly.
*/
+ if (!gtk_widget_get_realized (GTK_WIDGET (menu)))
{
GtkRequisition tmp_request;
GtkAllocation tmp_allocation = { 0, };