On Wayland we implement Client-Side Decorations if the compositors do not
implement SSDs. In that case, the destructors of the surfaces were called
in the wrong order, leading to a dereference of an already freed object.
We need to first destroy the subsurface before destroying the parent surface.
Related PR on kitty: https://github.com/kovidgoyal/kitty/pull/3066
Related issue on kitty: https://github.com/kovidgoyal/kitty/issues/3051Closes#1798.