Google Analytics Cross-domain tracking: Find and decorate iFrame

findAndDecorateIframes

function() {
  return function() {
    try { 
      var gobj = window[window.GoogleAnalyticsObject];
      var iframe = document.querySelector('#myIframe');
      var tracker, linker;
      if (gobj) {
        tracker = gobj.getAll()[0];
        linker = new window.gaplugins.Linker(tracker);
        iframe.src = linker.decorate(iframe.src);
      }
    } catch(e) {}
  }
}