Method makeEvent

src/core/runtime/runtime.js:690–694

(eventName, detail)

        }

        makeEvent(eventName, detail) {
            var evt = new Event(eventName, { bubbles: true, cancelable: true, composed: true });
            evt['detail'] = detail;
            return evt;
        }

        triggerEvent(elt, eventName, detail, sender) {
            detail = detail || {};