Use versioned deprecations more seriously
Use versioned deprecations more seriously

I invadvertendly introduced a dependency on a recent GLib recently,
by cherry-picking a fix that used new GLib API. This commit will
help catching such errors before release, by using the versioned
deprecation machinery to turn such events into build-time
warnings.

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