[glibmm] Gio::DBus::Message::get_unix_fd_list(): Add refreturn

[Kjell Ahlstedt <kjellahl src gnome org>]

commit ec96b5ac38beb97d2b84e9ed194c2688d68350ad
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Thu Mar 12 11:04:44 2020 +0100

    Gio::DBus::Message::get_unix_fd_list(): Add refreturn
    
    Fixes #68

 gio/src/dbusmessage.hg | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/gio/src/dbusmessage.hg b/gio/src/dbusmessage.hg
index 77b08f66..3a28cee7 100644
--- a/gio/src/dbusmessage.hg
+++ b/gio/src/dbusmessage.hg
@@ -109,8 +109,8 @@ public:
 
   _WRAP_METHOD(void set_body(const Glib::VariantBase& body), g_dbus_message_set_body)
 
-  _WRAP_METHOD(Glib::RefPtr<UnixFDList> get_unix_fd_list(), g_dbus_message_get_unix_fd_list, ifdef G_OS_UNIX)
-  _WRAP_METHOD(Glib::RefPtr<const UnixFDList> get_unix_fd_list() const, g_dbus_message_get_unix_fd_list, 
constversion, ifdef G_OS_UNIX)
+  _WRAP_METHOD(Glib::RefPtr<UnixFDList> get_unix_fd_list(), g_dbus_message_get_unix_fd_list, refreturn, 
ifdef G_OS_UNIX)
+  _WRAP_METHOD(Glib::RefPtr<const UnixFDList> get_unix_fd_list() const, g_dbus_message_get_unix_fd_list, 
refreturn, constversion, ifdef G_OS_UNIX)
   _WRAP_METHOD(void set_unix_fd_list(const Glib::RefPtr<UnixFDList>& fd_list), 
g_dbus_message_set_unix_fd_list, ifdef G_OS_UNIX)
 
 #ifdef G_OS_UNIX