widget-factory: Enable alpha in the color button
widget-factory: Enable alpha in the color button

This lets us verify that the theme treats the alpha scale fairly.

Adamovskiy/gtk,jigpu/gtk,jadahl/gtk,jadahl/gtk,Lyude/gtk-,ahodesuka/gtk,Lyude/gtk-,Lyude/gtk-,jessevdk/gtk,grubersjoe/adwaita,jigpu/gtk,chergert/gtk,Adamovskiy/gtk,alexlarsson/gtk,chergert/gtk,jadahl/gtk,Adamovskiy/gtk,jadahl/gtk,jadahl/gtk,jadahl/gtk,grubersjoe/adwaita,Adamovskiy/gtk,Lyude/gtk-,jessevdk/gtk,Lyude/gtk-,ahodesuka/gtk,jessevdk/gtk,davidgumberg/gtk,grubersjoe/adwaita,Lyude/gtk-,jigpu/gtk,jadahl/gtk,davidgumberg/gtk,Adamovskiy/gtk,davidgumberg/gtk,alexlarsson/gtk,jessevdk/gtk,jigpu/gtk,alexlarsson/gtk,jigpu/gtk,Adamovskiy/gtk,jigpu/gtk,ahodesuka/gtk,ahodesuka/gtk,alexlarsson/gtk,davidgumberg/gtk,ahodesuka/gtk,ahodesuka/gtk,ahodesuka/gtk,jessevdk/gtk,chergert/gtk,chergert/gtk,grubersjoe/adwaita,Lyude/gtk-,alexlarsson/gtk,jessevdk/gtk,chergert/gtk,grubersjoe/adwaita,chergert/gtk,Adamovskiy/gtk,alexlarsson/gtk,chergert/gtk,grubersjoe/adwaita,Adamovskiy/gtk,chergert/gtk,Lyude/gtk-,alexlarsson/gtk,davidgumberg/gtk,grubersjoe/adwaita,davidgumberg/gtk,davidgumberg/gtk,jigpu/gtk,jessevdk/gtk,grubersjoe/adwaita,ahodesuka/gtk,jigpu/gtk,alexlarsson/gtk,jadahl/gtk,davidgumberg/gtk