GtkFileChooserDialog: Avoid a bottom border in the dialog
GtkFileChooserDialog: Avoid a bottom border in the dialog

We recently started to respect border-width on the action_area
again, so set its border-width to 0 so it doesn't get in the way.

https://bugzilla.gnome.org/show_bug.cgi?id=722211

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