[rygel] server: Fix ambiguity of default "this"

[Jens Georg <jensgeorg src gnome org>]

commit ea01de7e5007427cf12097697ee3d34488cd18dd
Author: Jens Georg <jensg openismus com>
Date:   Tue Dec 11 16:52:21 2012 +0100

    server: Fix ambiguity of default "this"
    
    Fixes a warning in MediaExport when removing a file.

 src/librygel-server/rygel-media-container.vala |    7 +++++--
 1 files changed, 5 insertions(+), 2 deletions(-)
---
diff --git a/src/librygel-server/rygel-media-container.vala b/src/librygel-server/rygel-media-container.vala
index 3639d13..da51f8f 100644
--- a/src/librygel-server/rygel-media-container.vala
+++ b/src/librygel-server/rygel-media-container.vala
@@ -186,11 +186,14 @@ public abstract class Rygel.MediaContainer : MediaObject {
      * for this container, if items under it are removed or added, if
      * there are metadata changes to items under it, etc.
      */
-    public void updated (MediaObject object = this,
+    public void updated (MediaObject? object = null,
                          ObjectEventType event_type = ObjectEventType.MODIFIED,
                          bool sub_tree_update = false) {
         // Emit the signal that will start the bump-up process for this event.
-        this.container_updated (this, object, event_type, sub_tree_update);
+        this.container_updated (this,
+                                object != null ? object : this,
+                                event_type,
+                                sub_tree_update);
     }
 
     internal override DIDLLiteObject? serialize (Serializer serializer,