SDK / exoplayer

This is a breaking change if the annotation itself is in use in Kotlin
code. It's judged that the IntDefs in this commit are unlikely to be
referred to often in Kotlin code. This is because they're either:
- Related to esoteric parts of the library, or
- In a common part of the library but only returned from methods (and
  never passed to callback methods).

A follow-up change will fix the positions of existing usages to match
this new config.

#minor-release

PiperOrigin-RevId: 426410237