GtkDialog: Fix setting of default action
GtkDialog: Fix setting of default action

The recent reshuffling caused an ordering problem where we would
hide the action area before relocating the buttons to the header
bar. But hiding makes the default button loose its defaultness.
Rearrange things so that we move the buttons before hiding the
action area, and thus preserve the default.

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