[gtk+/portal] Annotation fix

[Matthias Clasen <matthiasc src gnome org>]

commit fe3a47ba4b0752e08f6c94acfcbdda827fee9610
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed Jul 6 23:25:32 2016 -0400

    Annotation fix
    
    parent is nullable in gtk_show_uri_on_window

 gtk/gtkshow.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/gtk/gtkshow.c b/gtk/gtkshow.c
index 6fb7e0f..1bec980 100644
--- a/gtk/gtkshow.c
+++ b/gtk/gtkshow.c
@@ -82,7 +82,7 @@ gtk_show_uri (GdkScreen    *screen,
 
 /**
  * gtk_show_uri_on_window:
- * @parent: parent window
+ * @parent: (allow-none): parent window
  * @uri: the uri to show
  * @timestamp: a timestamp to prevent focus stealing
  * @error: a #GError that is returned in case of errors