andrewlewis 470ec9e5d1 Init the ads manager for placeholder timelines
It looks like loading ad cue points would cause a source info refresh
causing the content media period load to be canceled, meaning we would
never get a non-placeholder timeline.

This changes ensures that the ads manager will still be initialized,
avoiding playback getting stuck when playing a ProgressiveMediaPeriod
with a preroll ad.

PiperOrigin-RevId: 298814758
2020-03-10 10:18:13 +00:00
..