chromium/third_party/blink/web_tests/media/csp-blocks-video.html

<!DOCTYPE html>
<title>Test that "Content-Security-Policy" on a media element is obeyed.</title>
<meta http-equiv="Content-Security-Policy" content="media-src 'none'">
<video></video>
<script src="../resources/testharness.js"></script>
<script src="../resources/testharnessreport.js"></script>
<script>
async_test(function(t) {
    var video = document.querySelector("video");
    video.src = "content/test.ogv";

    video.onloadedmetadata = t.unreached_func();
    video.onerror = t.step_func_done();
});
</script>