asutherland/child-frame.html

## child-frame.html
<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8">
    <script src="child-frame.js" type="application/javascript"></script>
  </head>
  <body id="content">
    <div id="expando-friend">
      Child!
    </div>
  </body>
</html>

## child-frame.js
function sendMessage() {
  var data = { foo: 'bar' };
  var message = new MessageEvent('message', { data, source: window });
  window.parent.dispatchEvent(message);
}

function makeGiantArray(megs) {
  var arr = new Uint8Array(megs * 1024 * 1024);
  for (var i = 0; i < arr.length; i++) {
    arr[i] = i&0xff;
  }
  return arr;
}

window.addEventListener('load', function() {
  // Let's save off giant arrays to the global and as a DOM expando.  Give them
  // different sizes so we can see which is the one being retained.
  window.jsGiantArray = makeGiantArray(2);
  document.getElementById('expando-friend').expandoGiantArray =
    makeGiantArray(3);

  sendMessage();
});

## parent-root.html
<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8">
    <script src="parent-root.js" type="application/javascript"></script>
  </head>
  <body id="content">
    <iframe id="child" src="child-frame.html" />
  </body>
</html>

## part-root.js
function killIframeSoon() {
  setTimeout(function() {
    var ifr = document.getElementById("child");
    ifr.parentNode.removeChild(ifr);
  });
}

window.addEventListener('message', function(event) {
  window.savedData = event.data;
  killIframeSoon();
});
	<!DOCTYPE html>
	<html>
	<head>
	<meta charset="UTF-8">
	<script src="child-frame.js" type="application/javascript"></script>
	</head>
	<body id="content">
	<div id="expando-friend">
	Child!
	</div>
	</body>
	</html>
	function sendMessage() {
	var data = { foo: 'bar' };
	var message = new MessageEvent('message', { data, source: window });
	window.parent.dispatchEvent(message);
	}

	function makeGiantArray(megs) {
	var arr = new Uint8Array(megs * 1024 * 1024);
	for (var i = 0; i < arr.length; i++) {
	arr[i] = i&0xff;
	}
	return arr;
	}

	window.addEventListener('load', function() {
	// Let's save off giant arrays to the global and as a DOM expando. Give them
	// different sizes so we can see which is the one being retained.
	window.jsGiantArray = makeGiantArray(2);
	document.getElementById('expando-friend').expandoGiantArray =
	makeGiantArray(3);

	sendMessage();
	});
	function killIframeSoon() {
	setTimeout(function() {
	var ifr = document.getElementById("child");
	ifr.parentNode.removeChild(ifr);
	});
	}

	window.addEventListener('message', function(event) {
	window.savedData = event.data;
	killIframeSoon();
	});