Fix: Map Editor - undo not updating tile count

Author: GeorgRottensteiner

C64Studio/Documents/MapEditor.cs

@@ -3159,6 +3159,7 @@ public void UpdateArea( int X, int Y, int Width, int Height )
                                                               Width * m_CurrentMap.TileSpacingY * 8,
                                                               Height * m_CurrentMap.TileSpacingY * 8 ) );
       RedrawMap();
+      RecalcTileUsageInCurrentMap();
     }