<!doctype html> <meta charset=utf-8> <title>MessageEvent</title> <script src=/resources/testharness.js></script> <script src=/resources/testharnessreport.js></script> <div id=log></div> <script> var prefixes = ['moz', 'ms', 'o', 'webkit']; prefixes.forEach(function(prefix) { var name = prefix + "InitMessageEvent"; test(function() { assert_false(name in MessageEvent.prototype); }, name + " on the prototype"); test(function() { var event = new MessageEvent("message"); assert_false(name in event); }, name + " on the instance"); }); </script>