chromium/third_party/blink/web_tests/plugins/object-onload-placeholder.html

<html>
<script src="../resources/testharness.js"></script>
<script src="../resources/testharnessreport.js"></script>
<body>
<object type="image/gif" data="resources/apple.gif" onload="loadHandler()"
    onerror="errorHandler()"></object>
<script>
var testobject = async_test("crbug.com/445557:error events aren't dispatched" +
    " for <object> elements");
function loadHandler() {
  setTimeout(() => {
    testobject.done();
  }, 0);
}
function errorHandler() {
  assert_unreached("Error event received");
};
</script>
</body>
</html>