Uncaught TypeError: Object #<HTMLDivElement> has no method 'webkitCancelFullScreen'

document.id('close-full-screen').addEvent('click', function() {
    document.id('full-screen').webkitCancelFullScreen();
});

document.id('close-full-screen').addEvent('click', function() {
  document.webkitCancelFullScreen();
});