list-box: fix typo in natural size computation
list-box: fix typo in natural size computation

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