Wacom's new "Pro Pen 3D" stylus is declared as a new stylus type within
libwacom: WSTYLUS_3D. Now that the Wacom panel supports arbitrary three-
button styli, we can add specific support for this new stylus type to
suppress the warning message that is generated.
https://bugzilla.gnome.org/show_bug.cgi?id=790028
Similar to CcWacomDevice vs GsdWacomDevice, CcWacomTool is meant to
replace the GsdWacomStylus object. There is a substantial difference
between these two objects, CcWacomTool offers constructor methods,
it expects the caller to maintain lifetime otherwise. while
GsdWacomStylus objects creation was rather fixed (GsdWacomDevice
created all possible styli on initialization). This latter model
doesn't help us use all the possibilities wrt wayland configurability.
