chromium/third_party/blink/web_tests/transitions/zero-duration-should-not-cancel.html

<!DOCTYPE html>
<body>
<script>
if (window.testRunner) {
  testRunner.dumpAsText();
  testRunner.waitUntilDone();
}

onload = function() {
  var target = document.body;
  var transitionEnd = 'rgb(255, 0, 0)';
  target.style.transition = 'all 1s';
  target.style.background = transitionEnd;
  target.offsetTop;

  target.style.transition = 'all 0s';
  target.offsetTop;
  
  document.documentElement.textContent =
      getComputedStyle(target).backgroundColor == transitionEnd ?
          'FAIL - Transition has completed' :
          'PASS';
  
  if (window.testRunner) {
    testRunner.notifyDone();
  }
};
</script>