pango: fix typo in PangoFontDescription to CSS conversion
pango: fix typo in PangoFontDescription to CSS conversion

We were mistakenly using pixels instead of points for this. This was not
visible in 3.20, but is now in 3.21.

cburschka/gtksourceview,uajain/gtksourceview,cburschka/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,cburschka/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,uajain/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,cburschka/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,uajain/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,cburschka/gtksourceview,GNOME/gtksourceview,uajain/gtksourceview,cburschka/gtksourceview,uajain/gtksourceview,uajain/gtksourceview,GNOME/gtksourceview,uajain/gtksourceview,cburschka/gtksourceview,uajain/gtksourceview,uajain/gtksourceview,cburschka/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,uajain/gtksourceview,cburschka/gtksourceview,GNOME/gtksourceview,cburschka/gtksourceview