Disable multi-device
Disable multi-device

The filter function we use to dispatch GDK events to Clutter has been
broken by the multi-device support in GDK; needs further investigation,
but right now we can disable multi-device support easily enough.

Distrotech/clutter-gtk,Distrotech/clutter-gtk,Distrotech/clutter-gtk,GNOME/clutter-gtk,GNOME/clutter-gtk