[rygel] engine-gst: Prevent critical after streaming

[Jens Georg <jensgeorg src gnome org>]

commit 3198d41d65e883a4f31185a05ec774d7ef73717b
Author: Jens Georg <mail jensge org>
Date:   Sat Jun 14 21:29:26 2014 +0200

    engine-gst: Prevent critical after streaming
    
    Signed-off-by: Jens Georg <mail jensge org>

 .../gstreamer/rygel-gst-data-source.vala           |    6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)
---
diff --git a/src/media-engines/gstreamer/rygel-gst-data-source.vala 
b/src/media-engines/gstreamer/rygel-gst-data-source.vala
index 1e536f6..2444a7f 100644
--- a/src/media-engines/gstreamer/rygel-gst-data-source.vala
+++ b/src/media-engines/gstreamer/rygel-gst-data-source.vala
@@ -78,7 +78,9 @@ internal class Rygel.GstDataSource : Rygel.DataSource, GLib.Object {
         // Unlock eventually frozen sink
         this.sink.cancellable.cancel ();
         this.pipeline.set_state (State.NULL);
-        Source.remove (this.bus_watch_id);
+        if (this.bus_watch_id != 0) {
+            Source.remove (this.bus_watch_id);
+        }
         Idle.add ( () => { this.done (); return false; });
     }
 
@@ -209,6 +211,8 @@ internal class Rygel.GstDataSource : Rygel.DataSource, GLib.Object {
 
                 return false;
             });
+
+            this.bus_watch_id = 0;
         }
 
         return ret;