Add all invisible surfaces to a hidden weston layer. Without this,
applications that are hidden from the beginning will not make any progess.

Also, always update properties. This is necessary for proper communication
with clients for invisible surfaces. This is probably also more correct:
When a layer is removed from a screen, then the area below is currently not
damaged. And the area below invisible views is damaged every time, not just
once when it it hidden.
Always call update_prop() instead. This will only trigger updates for any
visibility or geometry changes.

Signed-off-by: Michael Olbrich <m.olbrich@pengutronix.de>