The cursor code would destroy the buffer as soon as the cursor is
unrealized on X11 side.
Yet, the Wayland compositor may still be using the buffer as long as a
released callback has not been received.
Increase the reference counter on the pixmap to hold a reference on the
pixmap when attaching it to the surface and use the new pixmap release
callback mechanism to release that reference when the buffer is
released.
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Acked-by: Martin Peres <martin.peres@mupuf.org>
Reviewed-by: Michel Dänzer <mdaenzer@redhat.com>