<!doctype html>
<meta charset=utf-8>
<script>
'use strict';
window.onmessage = event => {
  // This is a bi-directional message passthrough. We pass "callGetBoxQuads"
  // messages down, and everything else back up.
  const iframe = document.querySelector("iframe");
  const goDown = !!event.data.callGetBoxQuads;
  const targetWindow = (goDown ? iframe.contentWindow : window.parent);

  targetWindow.postMessage(event.data, "*");
};
</script>
<style>
  body {
    margin: 0;
    padding: 0;
    background: lavender;
  }
  iframe {
    width: 150px;
    height: 150px;
    margin: 50px;
    border: 0;
  }
</style>
<iframe src="https://test1.example.com/browser/devtools/client/shared/test/doc_layoutHelpers_getBoxQuads2-c-and-e.html">
</iframe>
