popover: Hide widget first when disposing
popover: Hide widget first when disposing

In order to ensure invariants are kept.

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