docs: public PlaybackState getFurthestPlaybackState() {
          PlaybackState result = null;
          for (PlaybackState state : playbackStateMap.values()) {
              if (result == null || (!result.playing && state.playing) ||
                      (result.position < state.position) && (state.playing || !result.playing)) {
                  result = state;
              }
          }
          return result;
      }