[gi-demos] fix up the validation combobox
[gi-demos] fix up the validation combobox

davidmalcolm/pygobject,choeger/pygobject-cmake,MathieuDuponchelle/pygobject,pexip/pygobject,alexef/pygobject,sfeltman/pygobject,jdahlin/pygobject,choeger/pygobject-cmake,davibe/pygobject,nzjrs/pygobject,thiblahute/pygobject,MathieuDuponchelle/pygobject,alexef/pygobject,alexef/pygobject,sfeltman/pygobject,davibe/pygobject,sfeltman/pygobject,jdahlin/pygobject,davidmalcolm/pygobject,pexip/pygobject,thiblahute/pygobject,thiblahute/pygobject,GNOME/pygobject,nzjrs/pygobject,jdahlin/pygobject,pexip/pygobject,choeger/pygobject-cmake,GNOME/pygobject,nzjrs/pygobject,davibe/pygobject,davidmalcolm/pygobject,MathieuDuponchelle/pygobject,GNOME/pygobject,davibe/pygobject