SDK / exoplayer

*** Reason for rollforward ***

Rollforward after making sure the handler is created
from the playback thread and not from an app thread.

*** Original change description ***

Rollback of https://github.com/google/ExoPlayer/commit/e1beb1d1946bb8ca94f62578aee8cbadd97b6e2b

*** Original commit ***

Expose experimental offload scheduling

Add a new scheduling mode that stops ExoPlayer main loop
when the audio offload buffer is full and resume it when
it has been partially played.

This mode needs to be enabled and dissabled manually by the app
for now.

#exo-offload

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PiperOrigin-RevId: 316898804