added a way to remove observers

git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@2073 542714f4-19e9-0310-aa3c-eee0fc999fb1

src/java/com/threerings/media/AbstractMedia.java

@@ -1,5 +1,5 @@
 //
-// $Id: AbstractMedia.java,v 1.6 2002/12/12 23:54:59 shaper Exp $
+// $Id: AbstractMedia.java,v 1.7 2002/12/18 23:14:23 ray Exp $
 
 package com.threerings.media;
 
@@ -209,6 +209,16 @@ public abstract class AbstractMedia
         _observers.add(obs);
     }
 
+    /**
+     * Remove the specified observer from this media element.
+     */
+    protected void removeObserver (Object obs)
+    {
+        if (_observers != null) {
+            _observers.remove(obs);
+        }
+    }
+
     /**
      * Dumps this media to a String object.
      */