We had reports that the top software button area is hard to hit for those
using the trackpoint and clicking the buttons with their thumb.

Analysis of event recordings (3 different people) for left, right and middle
clicks shows that there is a significant amount of events up to about 10mm
(with outliers up to 12mm) from the top of the touchpad. That maps to 15%.

Interestingly, the middle button does not seem to need this, presumably the
haptic feedback of the little dots sticking out from the surface make hitting
the button easier. Its size is increased to 15% anyway, for simplicity and
because a sample set of 3 is too small to be definitive about this.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>