Tests nullable parameters to StorageEvent.initStorageEvent() On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". PASS event.__proto__ is StorageEvent.prototype event.initStorageEvent("storage", false, false, "key", "oldValue", "newValue", "url") PASS event.oldValue is "oldValue" PASS event.newValue is "newValue" event.initStorageEvent("storage", false, false, "key", null, null, "url") PASS event.oldValue is null PASS event.newValue is null event.initStorageEvent("storage", false, false, "key", "oldValue", "newValue", "url") PASS event.oldValue is "oldValue" PASS event.newValue is "newValue" event.initStorageEvent("storage", false, false, "key", undefined, undefined, "url") PASS event.oldValue is null PASS event.newValue is null PASS successfullyParsed is true TEST COMPLETE