Added sound group accessor to Sound.

git-svn-id: svn+ssh://src.earth.threerings.net/nenya/trunk@884 ed5b42cb-e716-0410-a449-f6a68f950b19

src/java/com/threerings/openal/Sound.java

@@ -40,6 +40,14 @@ public class Sound
         public void soundStarted (Sound sound);
     }
 
+    /**
+     * Returns a reference to the group to which the sound belongs.
+     */
+    public SoundGroup getGroup ()
+    {
+        return _group;
+    }
+
     /**
      * Returns the buffer of audio data associated with this sound.
      */