Drop outstanding cairo surfaces when window is made native
Drop outstanding cairo surfaces when window is made native

Any old cairo_surface referencing the old impl window will be wrong
when we make a window native, so drop it.

This fixes bug #599511

Distrotech/gtk2,simokivimaki/gtk,davidgumberg/gtk,grubersjoe/adwaita,johne53/MB3Gtk-2,grubersjoe/adwaita,bratsche/gtk-,chipx86/gtk,alexlarsson/gtk,ahodesuka/gtk,alexlarsson/gtk,bratsche/gtk-,alexlarsson/gtk,jigpu/gtk,ahodesuka/gtk,Lyude/gtk-,Distrotech/gtk2,Distrotech/gtk2,grubersjoe/adwaita,jigpu/gtk,Lyude/gtk-,jigpu/gtk,simokivimaki/gtk,jigpu/gtk,davidt/gtk,chipx86/gtk,Distrotech/gtk,Distrotech/gtk2,msteinert/gtk,grubersjoe/adwaita,simokivimaki/gtk,ebassi/gtk,alexlarsson/gtk,ahodesuka/gtk,chergert/gtk,Adamovskiy/gtk,Unity-Technologies/gtk,Unity-Technologies/gtk,jessevdk/gtk,Lyude/gtk-,davidgumberg/gtk,Sidnioulz/SandboxGtk,chergert/gtk,chergert/gtk,davidgumberg/gtk,jigpu/gtk,Distrotech/gtk,bratsche/gtk-,chergert/gtk,jessevdk/gtk,Sidnioulz/SandboxGtk,davidgumberg/gtk,chipx86/gtk,simokivimaki/gtk,jessevdk/gtk,davidt/gtk,ahodesuka/gtk,davidgumberg/gtk,Unity-Technologies/gtk,Lyude/gtk-,chipx86/gtk,jadahl/gtk,alexlarsson/gtk,chergert/gtk,ebassi/gtk,chipx86/gtk,chergert/gtk,Distrotech/gtk,jadahl/gtk,ahodesuka/gtk,Distrotech/gtk,johne53/MB3Gtk-2,jessevdk/gtk,Adamovskiy/gtk,davidt/gtk,grubersjoe/adwaita,simokivimaki/gtk,Sidnioulz/SandboxGtk,msteinert/gtk,ebassi/gtk,davidt/gtk,Lyude/gtk-,Lyude/gtk-,simokivimaki/gtk,davidt/gtk,chergert/gtk,msteinert/gtk,johne53/MB3Gtk-2,msteinert/gtk,grubersjoe/adwaita,Unity-Technologies/gtk,Adamovskiy/gtk,davidgumberg/gtk,jessevdk/gtk,Adamovskiy/gtk,ahodesuka/gtk,alexlarsson/gtk,Unity-Technologies/gtk,jadahl/gtk,jessevdk/gtk,Adamovskiy/gtk,Adamovskiy/gtk,Sidnioulz/SandboxGtk,Distrotech/gtk2,davidt/gtk,johne53/MB3Gtk-2,jigpu/gtk,alexlarsson/gtk,jadahl/gtk,bratsche/gtk-,ebassi/gtk,Adamovskiy/gtk,Lyude/gtk-,Lyude/gtk-,Distrotech/gtk2,grubersjoe/adwaita,jigpu/gtk,Sidnioulz/SandboxGtk,jigpu/gtk,davidgumberg/gtk,bratsche/gtk-,chergert/gtk,jadahl/gtk,jessevdk/gtk,Distrotech/gtk,msteinert/gtk,ahodesuka/gtk,alexlarsson/gtk,Adamovskiy/gtk,grubersjoe/adwaita,jadahl/gtk,msteinert/gtk,bratsche/gtk-,davidgumberg/gtk,jadahl/gtk,ebassi/gtk,Sidnioulz/SandboxGtk,johne53/MB3Gtk-2,jadahl/gtk,ahodesuka/gtk,ebassi/gtk