[gnome-chess] Reset the selected piece upon undo

[Sahil Sareen <ssareen src gnome org>]

commit 1f9239ec8c595fcc814a1bf86333d1112318146e
Author: Sahil Sareen <sahil sareen hotmail com>
Date:   Sun Jan 11 00:13:03 2015 +0530

     Reset the selected piece upon undo
    
    The selected piece should be reset when the
    player presses undo.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=734181

 src/gnome-chess.vala |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
---
diff --git a/src/gnome-chess.vala b/src/gnome-chess.vala
index dbe5275..65a3cd4 100644
--- a/src/gnome-chess.vala
+++ b/src/gnome-chess.vala
@@ -1484,6 +1484,10 @@ public class ChessApplication : Gtk.Application
 
     public void undo_move_cb ()
     {
+        // No piece should be selected now
+        scene.selected_rank = -1;
+        scene.selected_file = -1;
+
         if (opponent != null)
             human_player.undo ();
         else