[gnome-contacts] Fix several Gtk-CRITICALS (bug 737627).

[Niels De Graef <nielsdg src gnome org>]

commit 1f864b0ee2eb305a76e2f5e1bbba176bf997f113
Author: Niels De Graef <nielsdegraef gmail com>
Date:   Mon Jun 26 20:39:59 2017 +0200

    Fix several Gtk-CRITICALS (bug 737627).
    
    Remove the custom_iter field since it was never assigned to and use null
    instead.

 src/contacts-types.vala |    5 ++---
 1 files changed, 2 insertions(+), 3 deletions(-)
---
diff --git a/src/contacts-types.vala b/src/contacts-types.vala
index b50d22a..4cef86a 100644
--- a/src/contacts-types.vala
+++ b/src/contacts-types.vala
@@ -49,7 +49,6 @@ public class Contacts.TypeSet : Object  {
 
   public Gtk.ListStore store;
   private TreeIter other_iter;
-  private TreeIter custom_iter;
 
   private TypeSet () {
     display_name_hash = new HashTable<unowned string, Data> (str_hash, str_equal);
@@ -69,7 +68,7 @@ public class Contacts.TypeSet : Object  {
 
     data.in_store = true;
     if (is_custom)
-      store.insert_before (out data.iter, custom_iter);
+      store.insert_before (out data.iter, null);
     else
       store.append (out data.iter);
 
@@ -135,7 +134,7 @@ public class Contacts.TypeSet : Object  {
       return;
     }
 
-    store.insert_before (out iter, custom_iter);
+    store.insert_before (out iter, null);
     store.set (iter, 0, label, 1, null);
     custom_hash.insert (label, iter);
   }