Fix x/y coordinates for extended events.
Fix x/y coordinates for extended events.

Extended events were being reported to virtual windows without taking into
account the position of the virtual window inside the native one.

https://bugzilla.gnome.org/show_bug.cgi?id=588649

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