[chronojump] Fix on genericWin treeview context menu

[Xavier de Blas <xaviblas src gnome org>]

commit 743b605b0d272d82d6918257301b1cca975ef195
Author: Xavier de Blas <xaviblas gmail com>
Date:   Wed Jun 8 20:40:52 2016 +0200

    Fix on genericWin treeview context menu

 src/gui/genericWindow.cs |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/src/gui/genericWindow.cs b/src/gui/genericWindow.cs
index 8b160fc..94aa544 100644
--- a/src/gui/genericWindow.cs
+++ b/src/gui/genericWindow.cs
@@ -748,6 +748,8 @@ public class GenericWindow
                        myItem = new MenuItem ( Catalog.GetString("Delete selected") );
                        myItem.Activated += on_delete_selected_clicked;
                        myMenu.Attach( myItem, 0, 1, 0, 1 );
+               } else {
+                       return; //don't show nothing if there are no options
                }
 
                myMenu.Popup();