[tracker/wip/ricotz/type-args] libtracker-sparql: Fix type-arguments issue in *intermediate-c.vapi

[Rico Tzschichholz <ricotz src gnome org>]

commit c126a320c257fdc9da508ca6cd064c11dc1c690f
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Thu Sep 20 15:52:29 2018 +0200

    libtracker-sparql: Fix type-arguments issue in *intermediate-c.vapi

 src/libtracker-sparql/libtracker-sparql-intermediate-c.vapi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/libtracker-sparql/libtracker-sparql-intermediate-c.vapi 
b/src/libtracker-sparql/libtracker-sparql-intermediate-c.vapi
index 4dc894a27..25800f0cf 100644
--- a/src/libtracker-sparql/libtracker-sparql-intermediate-c.vapi
+++ b/src/libtracker-sparql/libtracker-sparql-intermediate-c.vapi
@@ -51,7 +51,7 @@ namespace Tracker {
                public void add_string (string predicate, string object);
                public void add_uri (string predicate, string object);
 
-               public GLib.List<GLib.Value> get_values (string predicate);
+               public GLib.List<GLib.Value?> get_values (string predicate);
 
                public bool get_first_boolean (string predicate);
                public double get_first_double (string predicate);