shm: wl_shm_buffer_get_data() requires a valid pool.
shm: wl_shm_buffer_get_data() requires a valid pool.

There's no situation where a shm buffer without a pool makes sense,
so we enforce the pool's existence a little more rigidly.

Acked-by: Pekka Paalanen <0f6ae7001e34c37b02fb2c1c2573ddf8f442136a@collabora.co.uk>
Signed-off-by: Derek Foreman <2f97e0f0bc172406aab8ccd42dab54c95bab8759@osg.samsung.com>
Reviewed-by: Giulio Camuffo <65adf162ac3b23aefeb12d72b964c762bc76d738@gmail.com>

mchalupa/wayland,sir-murray/wayland,sir-murray/wayland,mchalupa/wayland,mchalupa/wayland,sir-murray/wayland