In some cases we need to update the PlaybackParameters at period
boundaries, for example when switching from live to VOD and live
playback speed adjustment was still active at the point of switching.

Currently, we send the update when the playing MediaPeriod changes in
EPII, which is slightly too late because the new speed gets only applied
after the entire existing AudioTrack buffer has been played out.

We can time the update slightly better by updating the values at the
point where we change the reading period. This makes the update slightly
too early because it also applies to all samples currently in the
decoder. But generally, this is a lot better because the time spent
in the decoder is likely to be considerably lower than the duration of
the AudioTrack buffer.

Note that this change isn't perfectly aligning to the period boundary,
but reduces the number of samples with the wrong speed to a minimum.
If we are getting around to add additional code that allows updating
the speed at exactly the boundary, it also needs to be triggered from
the reading period update, so the new code location is also helpful in
the future.

Issue: google/ExoPlayer#9018
PiperOrigin-RevId: 424540551

Ad playback shouldn't be affected by manual speed adjustments set
by the user. This change enforces unit speed for ad playback.

Issue: google/ExoPlayer#9018
PiperOrigin-RevId: 424546258

In some cases we need to update the PlaybackParameters at period
boundaries, for example when switching from live to VOD and live
playback speed adjustment was still active at the point of switching.

Currently, we send the update when the playing MediaPeriod changes in
EPII, which is slightly too late because the new speed gets only applied
after the entire existing AudioTrack buffer has been played out.

We can time the update slightly better by updating the values at the
point where we change the reading period. This makes the update slightly
too early because it also applies to all samples currently in the
decoder. But generally, this is a lot better because the time spent
in the decoder is likely to be considerably lower than the duration of
the AudioTrack buffer.

Note that this change isn't perfectly aligning to the period boundary,
but reduces the number of samples with the wrong speed to a minimum.
If we are getting around to add additional code that allows updating
the speed at exactly the boundary, it also needs to be triggered from
the reading period update, so the new code location is also helpful in
the future.

Issue: #9018
PiperOrigin-RevId: 424540551

Ad playback shouldn't be affected by manual speed adjustments set
by the user. This change enforces unit speed for ad playback.

Issue: #9018
PiperOrigin-RevId: 424546258