kiosk-shell: Don't assume a valid output
Turns out kiosk_shell_output_set_active_surface_tree() requires having a valid output which as seen in the wild might not be case. Provents an illegal dereference on an invalid shoutput.
Fixes: #920 (closed) Signed-off-by: Marius Vlad marius.vlad@collabora.com
Edited by Marius Vlad