text: (function (window, document) {
    var iframe = document.getElementById('prototype');
    var Editor = document.Editor;
  
    var iFrameController = {
      iframeWin: iframe.contentWindow,
    
      sendToIframe: function(message) {
        this.iframeWin.postMessage(message, prototypeOrigin);
      },
  
      init: function() {
        // set iframe to height of editor's column
        var contentHeight = document.getElementById('content').getBoundingClientRect().height;
  
        iframe.style.height = contentHeight + 'px';
      }
    };
  
    Editor.iFrameController = iFrameController;
  })(window, document);
  