[gnome-builder] preferences: add missing G-I introspection

[Christian Hergert <chergert src gnome org>]

commit 60680b25c80502e10336aba4c02429f56cc3e493
Author: Christian Hergert <chergert redhat com>
Date:   Sun Oct 30 02:14:45 2016 -0700

    preferences: add missing G-I introspection

 libide/preferences/ide-preferences.c |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)
---
diff --git a/libide/preferences/ide-preferences.c b/libide/preferences/ide-preferences.c
index 54848c5..08937fe 100644
--- a/libide/preferences/ide-preferences.c
+++ b/libide/preferences/ide-preferences.c
@@ -108,6 +108,11 @@ ide_preferences_add_spin_button (IdePreferences *self,
   return IDE_PREFERENCES_GET_IFACE (self)->add_spin_button (self, page_name, group_name, schema_id, key, 
path, title, subtitle, keywords, priority);
 }
 
+/**
+ * ide_preferences_add_custom:
+ * @keywords: (nullable): Optional keywords for search
+ *
+ */
 guint
 ide_preferences_add_custom (IdePreferences *self,
                             const gchar    *page_name,