Placing the kings to the center of the board when the game is over

Here is the link I finally found which gives good explanation: http://www.digitalgametechnology.com/index.php/support1/frequently-asked-questions/361-boards/general/162-how-is-the-result-of-a-game-indicated-on-a-dgt-e-board?mavikthumbnails_display_ratio=1.5
I'm watching London Chess Classic and when a game is finished a woman walks to the board and moves both kings to the central squares.
What is that about?