Untitled

function setIframeUrl() {
  var iframeDoc = this.iframeEl.contentWindow.document;
  iframeDoc.open().write(
    '<body onload="window.location.href='' + this.src + ''; parent.postMessage(
       '' + this.iframeLoadedMessage + '', '*')">
     </body>
     <script>n window.document.onreadystatechange = function () {
       if(window.document.readyState === 'complete') {
         parent.postMessage('' + this.iframeOnReadyStateChangeMessage + '', '*')
       }};
     </script>'
  );

  iframeDoc.close();
},

<html>
  <body class="foo">
    Hello World
  </body>
</html>