150e54b560
If a source is removed from the playlist, the player may still call createPeriod for a period of the removed source as long as the new timeline hasn't been handled by the player. These events are stale and can be ignored by using a dummy media source. The stale media period will be released when the player handles the updated timeline. Issue:#4871 ------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=214787090