display: Without a grab op let events go through clutter too

We want events to reach clutter no only when there a compositor modal
grab but also when no grab op is in effect.

https://bugzilla.gnome.org/show_bug.cgi?id=712247
wayland: Update internal wayland state unconditionally

Things like idle times and the cursor position need to be updated even
if there's a mutter grab in effect.

https://bugzilla.gnome.org/show_bug.cgi?id=712247