gdkwindow: Squash a leak in the subsurface case
gdkwindow: Squash a leak in the subsurface case

cairo_surface_create_for_rectangle takes a ref on the parent surface,
so we need to drop ours.

Rename get_window_surface to ref_window_surface to make the code more
clear and to stop this error from happening again.

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