When Xephyr is embedded into another application (e.g. in xoo), the
input events may come from the parent Window instead of our own. So make
sure we find the host screen in that case as well instead of crashing.
Signed-off-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
Reviewed-by: Daniel Stone <daniel@fooishbar.org>
cf05db8dde