proper window title;

--- a/src/Pure/ML/ml_statistics.scala	Sat Jan 12 22:08:38 2013 +0100
+++ b/src/Pure/ML/ml_statistics.scala	Sat Jan 12 22:14:29 2013 +0100
@@ -109,6 +109,7 @@
       Swing_Thread.later {
         new Frame {
           iconImage = Isabelle_System.get_icon().getImage
+          title = "ML statistics"
           contents = Component.wrap(new ChartPanel(c))
           visible = true
         }