chromium/third_party/blink/web_tests/media/video-without-controls-not-selected.html

<!DOCTYPE html>
<title>Tests that the containing focusable div is selected instead of the video when there are no controls.</title>
<script src="../resources/testharness.js"></script>
<script src="../resources/testharnessreport.js"></script>
<script src="media-controls.js"></script>
<div id="container" tabindex=0>
  <video></video>
</div>
<script>
async_test(t => {
  const video = document.querySelector("video");
  window.addEventListener('load', t.step_func(() => {
    // Click on the video.
    var coords = elementCoordinates(video);
    singleTapAtCoordinates(coords[0], coords[1], t.step_func_done(() => {

      // There should be no focus on the video, only the containing div.
      assert_equals(document.activeElement, document.getElementById("container"));
    }));
  }));
});
</script>