[PATCH] dix: avoid NULL-pointer dereference on button-only devices (#38313)

[Chase Douglas]

On 02/21/2012 09:49 PM, Peter Hutterer wrote:
> And for such devices simply take the last.valuators[] which must be valid at
> all times anyway. UpdateSlaveDeviceCoords takes care of that.
> 
> X.Org Bug 38313 <http://bugs.freedesktop.org/show_bug.cgi?id=38313>
> 
> Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>

Makes sense and looks right to me.

Reviewed-by: Chase Douglas <chase.douglas at canonical.com>