Adding in function to remove unifinder observer.

calendar/resources/content/unifinder.js

@@ -150,6 +150,16 @@ function prepareCalendarUnifinder( )
    gICalLib.addObserver( unifinderEventDataSourceObserver );
 }
 
+/**
+*   Called when the calendar is unloaded
+*/
+
+function finishCalendarUnifinder( eventSource )
+{
+   gICalLib.removeObserver( unifinderEventDataSourceObserver  );
+}
+
+
 /**
 *   Helper function to display event dates in the unifinder
 */