With gtk+ >= 3.22 trackpoints are classified separately from mice so
we need to handle them here. Also, remove the default case so that we
get a compilation warning in case this happens again.
In the future we might want to expose this further if we start adding
trackpoint specific UI.
https://bugzilla.gnome.org/show_bug.cgi?id=776660
GsdWacomDevice has been updated, dragging GsdDeviceManager as a dependency
from g-s-d, which has been added to panels/common, and compiled as a
separate static libary, which is used by the wacom and mouse modules.
gsd-input-helper.[ch] is now in such library and has been removed from
the panel directories.
https://bugzilla.gnome.org/show_bug.cgi?id=743196
