[vala/0.40] glib-2.0: Bind strcmp0 as GLib.CompareFunc<string?>

[Rico Tzschichholz <ricotz src gnome org>]

commit d8acfac7141cc13b9f08942ad41e702afde3d20c
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Mon Jul 1 11:10:35 2019 +0200

    glib-2.0: Bind strcmp0 as GLib.CompareFunc<string?>
    
    Allows proper usage with experimental non-null
    
    Fixes https://gitlab.gnome.org/GNOME/vala/issues/810

 vapi/glib-2.0.vapi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/vapi/glib-2.0.vapi b/vapi/glib-2.0.vapi
index ede9b8d3f..6964cd9b4 100644
--- a/vapi/glib-2.0.vapi
+++ b/vapi/glib-2.0.vapi
@@ -4626,7 +4626,7 @@ namespace GLib {
 
        [Version (since = "2.16")]
        [CCode (cname = "((GCompareFunc) g_strcmp0)")]
-       public static GLib.CompareFunc<string> strcmp;
+       public static GLib.CompareFunc<string?> strcmp;
 
        public delegate G CopyFunc<G> (G src);