<!doctype html>
<title>MediaController events task source</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<div id="log"></div>
<script>
async_test(function(t) {
  // Both MediaControllers should use the DOM manipulation task source, so the
  // events should fire in the same order as the attributes are modified.
  var mc1 = new MediaController();
  var mc2 = new MediaController();
  mc1.volume = 0;
  mc2.volume = 0;
  mc1.volume = 1;
  mc2.volume = 1;
  var targets = [];
  var callback = t.step_func(function(event) {
    targets.push(event.target);
    if (targets.length == 4) {
      assert_array_equals(targets, [mc1, mc2, mc1, mc2]);
      t.done();
    }
  });
  mc1.addEventListener('volumechange', callback);
  mc2.addEventListener('volumechange', callback);
});
</script>