scrollgrandchild-parent.html | Explore in Territory

<html>
<head>
  <style>
    #child {
      width: 150px;
      height: 300px;
      border: none;
      transform: translate(100px, 100px);
    }
  </style>
</head>
<body>
  <iframe id="child" src="scrollgrandchild-inner.html"></iframe>
</body>
</html>

chromium/third_party/blink/web_tests/compositing/iframes/resources/scrollgrandchild-parent.html