SDK / exoplayer

With HLS chunkless preparation, audio formats may have no value
for channel count. In this case, the DefaultAudioSink will either query
the platform for a supported channel count (API 29+) or assume a max
channel count based on the encoding spec in order to decide whether the
audio format can be played with audio passthrough.

Issue: google/ExoPlayer#10204

#minor-release

PiperOrigin-RevId: 453644548
(cherry picked from commit b3b57bc9)