[vala] gobject-2.0: Fix binding of ParamSpec.get_default_value()

[Rico Tzschichholz <ricotz src gnome org>]

commit af03c0dfbe7a426d95b4a7a9f99d96db6357437a
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Thu Jul 21 15:15:21 2016 +0200

    gobject-2.0: Fix binding of ParamSpec.get_default_value()

 vapi/gobject-2.0.vapi |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/vapi/gobject-2.0.vapi b/vapi/gobject-2.0.vapi
index da09ab1..997a9e0 100644
--- a/vapi/gobject-2.0.vapi
+++ b/vapi/gobject-2.0.vapi
@@ -221,7 +221,7 @@ namespace GLib {
                public GLib.Type value_type;
                public unowned string get_blurb ();
                [Version (since = "2.38")]
-               public unowned GLib.Value get_default_value ();
+               public unowned GLib.Value? get_default_value ();
                public unowned string get_name ();
                [Version (since = "2.46")]
                public GLib.Quark get_name_quark ();