[PATCH weston] shell: Add a lock binding

[Bill Spitzak]

Kristian Høgsberg wrote:

> The problem then is that the key release of the binding will now count
> as activity and undo the lock.  I think we'll need a custom grab (see
> weston_compositor_run_key_binding()) that triggers the lock on release
> of the last key in the binding.  Or maybe add a "virtual modifier",
> say MODIFIER_RELEASE, to make the binding code trigger the binding on
> release instead.

Could you just have all release events not count as "activity"?