Avoid copying touchpoints, and only check until we find a match.

Change-Id: I46fad782e93fe1f940acec05f4e1bb4afb5be230
Reviewed-by: Andrew Knight <andrew.knight@digia.com>
Reviewed-by: Shawn Rutledge <shawn.rutledge@digia.com>
Reviewed-by: Laszlo Agocs <laszlo.agocs@digia.com>
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@digia.com>