cssmatcher: Simplify code
cssmatcher: Simplify code

Instead of copy/paste, pass the only difference as an argument

The code still doesn't work right, but at least it's easier to fix now.

alexlarsson/gtk,davidgumberg/gtk,Adamovskiy/gtk,jadahl/gtk,jadahl/gtk,jadahl/gtk,jigpu/gtk,chergert/gtk,grubersjoe/adwaita,grubersjoe/adwaita,jigpu/gtk,jigpu/gtk,Adamovskiy/gtk,chergert/gtk,grubersjoe/adwaita,Adamovskiy/gtk,alexlarsson/gtk,chergert/gtk,Adamovskiy/gtk,chergert/gtk,davidgumberg/gtk,chergert/gtk,jigpu/gtk,alexlarsson/gtk,jadahl/gtk,jigpu/gtk,jadahl/gtk,davidgumberg/gtk,grubersjoe/adwaita,Adamovskiy/gtk,jadahl/gtk,alexlarsson/gtk,chergert/gtk,davidgumberg/gtk,grubersjoe/adwaita,jadahl/gtk,chergert/gtk,davidgumberg/gtk,alexlarsson/gtk,Adamovskiy/gtk,jigpu/gtk,grubersjoe/adwaita,alexlarsson/gtk,Adamovskiy/gtk,grubersjoe/adwaita,jigpu/gtk,alexlarsson/gtk,grubersjoe/adwaita,alexlarsson/gtk,chergert/gtk,davidgumberg/gtk,jadahl/gtk,jigpu/gtk,davidgumberg/gtk,davidgumberg/gtk,Adamovskiy/gtk