Fix fingerpaint example for platforms that don't support touch device
area and pressure by setting default size of drawn ellipse.

Change-Id: I884c688aa8ef98debf24876dbefaa4cff43a86a2
Reviewed-by: Fabian Bumberger <fbumberger@rim.com>
Reviewed-by: Shawn Rutledge <shawn.rutledge@digia.com>