video 标签制定了 show-casting-button 属性，展示了投屏按钮

点击完，选择好电视之后，就直接显示投屏失败

试了两个电视都这样，麻烦官方查一下

拿到了报错信息

{"type": "castingstatechange", "timeStamp": 68273, "target": {"id": "video-4523", "offsetLeft": 0, "offsetTop": 0, "dataset": {"id": 4523}}, "currentTarget": {"id": "video-4523", "offsetLeft": 0, "offsetTop": 0, "dataset": {"id": 4523}}, "mark": {}, "detail": {"viewId": 447864531, "state": "fail"}, "mut": false, "_userTap": false, "__evName": "castingstatechange"}