SDK / exoplayer

This adds the forwarding logic for most setters in SimpleExoPlayer
in the same style as the existing logic for setPlayWhenReady.

This change doesn't implement the setters for modifying media items,
seeking and releasing yet as they require additional handling that
goes beyond the repeated implementation pattern in this change.

PiperOrigin-RevId: 492124399
(cherry picked from commit e598a17b)