
These are the remaining setter operations. They all share the same logic that handles playlist and/or position changes. The logic to create the placeholder state is mostly copied from ExoPlayerImpl's maskTimelineAndPosition and getPeriodPositonUsAfterTimelineChanged. PiperOrigin-RevId: 496364712 (cherry picked from commit 09d37641d1ef3b8cf26dc39cfcd317ebe3ef5c79)