[gtkmm] C++11: Use override instead of virtual.

[Murray Cumming <murrayc src gnome org>]

commit fb7b7697f8028cbf12fab1b68e6163984c3de94c
Author: Murray Cumming <murrayc murrayc com>
Date:   Thu Dec 24 12:45:29 2015 +0100

    C++11: Use override instead of virtual.
    
    This ensures that the base class is really virtual.

 gtk/gtkmm/listviewtext.h |    2 +-
 gtk/gtkmm/object.h       |    2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/gtk/gtkmm/listviewtext.h b/gtk/gtkmm/listviewtext.h
index c055425..43f00d4 100644
--- a/gtk/gtkmm/listviewtext.h
+++ b/gtk/gtkmm/listviewtext.h
@@ -43,7 +43,7 @@ class ListViewText : public Gtk::TreeView
 public:
 
   ListViewText(guint columns_count, bool editable = false, Gtk::SelectionMode mode = Gtk::SELECTION_SINGLE);
-  virtual ~ListViewText() noexcept;
+  ~ListViewText() noexcept override;
 
   /** Adds a title to column @a column.
    * @param column the column number.
diff --git a/gtk/gtkmm/object.h b/gtk/gtkmm/object.h
index e5b46a9..c72d6fc 100644
--- a/gtk/gtkmm/object.h
+++ b/gtk/gtkmm/object.h
@@ -74,7 +74,7 @@ class GTKMM_API Object : public Glib::Object
   Object(Object&& src) noexcept;
   Object& operator=(Object&& src) noexcept;
 
-  virtual ~Object() noexcept;
+  ~Object() noexcept override;
 
 #ifndef DOXYGEN_SHOULD_SKIP_THIS