When delegating EMSG samples in `HlsSampleStreamWrapper`,
the offset passed into `sampleMetadata(..)` of the delegate
`TrackOutput` must be zero because it is called immediately
after `sampleData(..)` is called.
The condition to trigger this issue is that more than one
metadata samples are pending in `pendingMetadataSampleInfos`
of `FragmentedMp4Extractor` which produces non-zero offsets.
Issue: androidx/media#1002
Issue: androidx/media#1203
PiperOrigin-RevId: 623210835
5a84e09a0e