open-with: don't override the class signal handler, as it's RUN_LAST
open-with: don't override the class signal handler, as it's RUN_LAST

And explain why in a comment; basically we want our handler to always
run before client code.

Adamovskiy/gtk,msteinert/gtk,ahodesuka/gtk,ahodesuka/gtk,Sidnioulz/SandboxGtk,jigpu/gtk,ahodesuka/gtk,davidgumberg/gtk,Distrotech/gtk2,chergert/gtk,ahodesuka/gtk,alexlarsson/gtk,jadahl/gtk,ebassi/gtk,Lyude/gtk-,jessevdk/gtk,grubersjoe/adwaita,ebassi/gtk,chergert/gtk,jessevdk/gtk,davidgumberg/gtk,Distrotech/gtk2,davidt/gtk,Sidnioulz/SandboxGtk,ahodesuka/gtk,grubersjoe/adwaita,davidt/gtk,Distrotech/gtk2,chergert/gtk,ebassi/gtk,Lyude/gtk-,jessevdk/gtk,jadahl/gtk,alexlarsson/gtk,grubersjoe/adwaita,alexlarsson/gtk,Lyude/gtk-,bratsche/gtk-,Sidnioulz/SandboxGtk,jessevdk/gtk,jessevdk/gtk,grubersjoe/adwaita,chergert/gtk,ebassi/gtk,grubersjoe/adwaita,simokivimaki/gtk,davidt/gtk,jigpu/gtk,simokivimaki/gtk,davidt/gtk,jigpu/gtk,Distrotech/gtk2,jessevdk/gtk,Distrotech/gtk2,davidt/gtk,davidgumberg/gtk,ahodesuka/gtk,Adamovskiy/gtk,bratsche/gtk-,jadahl/gtk,simokivimaki/gtk,davidgumberg/gtk,Adamovskiy/gtk,msteinert/gtk,jadahl/gtk,bratsche/gtk-,bratsche/gtk-,grubersjoe/adwaita,jadahl/gtk,jadahl/gtk,Lyude/gtk-,Adamovskiy/gtk,Sidnioulz/SandboxGtk,grubersjoe/adwaita,jessevdk/gtk,Lyude/gtk-,davidt/gtk,jigpu/gtk,ebassi/gtk,chergert/gtk,grubersjoe/adwaita,Adamovskiy/gtk,Distrotech/gtk2,davidgumberg/gtk,msteinert/gtk,msteinert/gtk,bratsche/gtk-,Sidnioulz/SandboxGtk,davidgumberg/gtk,simokivimaki/gtk,msteinert/gtk,ahodesuka/gtk,jigpu/gtk,chergert/gtk,Lyude/gtk-,jigpu/gtk,jadahl/gtk,jigpu/gtk,alexlarsson/gtk,chergert/gtk,bratsche/gtk-,Adamovskiy/gtk,Sidnioulz/SandboxGtk,chergert/gtk,Lyude/gtk-,alexlarsson/gtk,alexlarsson/gtk,davidgumberg/gtk,alexlarsson/gtk,Adamovskiy/gtk,ebassi/gtk,ahodesuka/gtk,simokivimaki/gtk,Adamovskiy/gtk,simokivimaki/gtk,jigpu/gtk,jadahl/gtk,davidgumberg/gtk,msteinert/gtk,Lyude/gtk-,alexlarsson/gtk