[connections/decouple-display-name-and-address: 1/2] database: Store keys also when their string value is null

[Felipe Borges <felipeborges src gnome org>]

commit aa154a91fee76baeeb7814159aa99032374a34a2
Author: Felipe Borges <felipeborges gnome org>
Date:   Tue May 18 16:07:17 2021 +0200

    database: Store keys also when their string value is null
    
    An empty Connection.display_name is still valid.

 src/database.vala | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)
---
diff --git a/src/database.vala b/src/database.vala
index ff494ee..352a4f2 100644
--- a/src/database.vala
+++ b/src/database.vala
@@ -120,9 +120,10 @@ namespace Connections {
 
             connection.get_property (property_name, ref value);
 
-            if (value.type () == typeof (string))
-                keyfile.set_string (connection.uuid, property_name, value.get_string ());
-            else if (value.type () == typeof (bool))
+            if (value.type () == typeof (string)) {
+                var vstring = (value.get_string () == null ? "" : value.get_string ());
+                keyfile.set_string (connection.uuid, property_name, vstring);
+            } else if (value.type () == typeof (bool))
                 keyfile.set_boolean (connection.uuid, property_name, value.get_boolean ());
             else if (value.type () == typeof (uint64))
                 keyfile.set_uint64 (connection.uuid, property_name, value.get_uint64 ());