SDK / exoplayer

renderOutputFrame actually renders frames to an output surface. We'll soon have
a releaseOutputFrame method, that would release resources associated with an
output time, so rename this to disambiguate the two methods.

Also rename onOutputFrameAvailable to onOutputFrameAvailableForRendering, to
make it clear this is not available for "release"

This change should be a renaming-only change and have no functional differences.

PiperOrigin-RevId: 527844947