[banshee] PlayQueue: fix another GtkCRITICAL at shutdown (bgo#710266)

[Andrés Aragoneses <aaragoneses src gnome org>]

commit c721e23213cf305f445885ece56fc0b8c4b82279
Author: Andrés G. Aragoneses <knocte gmail com>
Date:   Mon Oct 21 22:30:19 2013 +0200

    PlayQueue: fix another GtkCRITICAL at shutdown (bgo#710266)
    
    This is the third warning/GtkCritical of the similar kind as the
    ones raised in bgo#710266, which was also caused when closing
    Banshee after pausing a video. This time the fix is similar to
    the previous one[1]: unsubscribing from an event at Dispose time,
    which was causing this particular stacktrace: [2].
    
    [1] https://git.gnome.org/browse/banshee/commit/?id=dae6be2d04662b4f9c17261213c394aa635580bf
    [2] https://bugzilla.gnome.org/show_bug.cgi?id=710266#c2

 .../Banshee.PlayQueue/PlayQueueActions.cs          |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/src/Extensions/Banshee.PlayQueue/Banshee.PlayQueue/PlayQueueActions.cs 
b/src/Extensions/Banshee.PlayQueue/Banshee.PlayQueue/PlayQueueActions.cs
index 94c54ca..7bab12d 100644
--- a/src/Extensions/Banshee.PlayQueue/Banshee.PlayQueue/PlayQueueActions.cs
+++ b/src/Extensions/Banshee.PlayQueue/Banshee.PlayQueue/PlayQueueActions.cs
@@ -122,6 +122,7 @@ namespace Banshee.PlayQueue
             if (disposing) {
                 playqueue.Updated -= OnUpdated;
                 ServiceManager.SourceManager.ActiveSourceChanged -= OnSourceUpdated;
+                ServiceManager.PlaybackController.SourceChanged -= OnPlaybackSourceChanged;
             }
             base.Dispose (disposing);
         }