This has been broken since https://github.com/google/ExoPlayer/commit/c3d6be3afdd7c0ca68dba15e443bc64aa3f61073 and broken for ICY (where I noticed the problem) since https://github.com/google/ExoPlayer/commit/5695bae9d8fde5e156fd38fa552e266c5611c71f. ICY symptom is that we see no repeated metadata, because the Icy-MetaData:1 header doesn't make it to the server so we never get back icy-metaint. PiperOrigin-RevId: 285379234
