Instead of only passing absolute pointer coordinates, effectively
loosing motion event data, pass a struct that can potentially contain
different types of motion events, currently being absolute and relative.
A helper function to get resulting absolute coordinates was added for
when previous callbacks simply used the (x, y) coordinates.
Signed-off-by: Jonas Ådahl <jadahl@gmail.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Derek Foreman <derekf@osg.samsung.com>