Exoplayer Changes:
* Fixes automatic rendition selection staying on the lowest quality tier of content whose rendition ladder is split over several DASH AdaptationSets, as content with HDCP fallback is. Such content now adapts across the whole ladder. An application that plays HDCP fallback content must restrict rendition selection to SD while the video output of the device is not HDCP protected, because the higher tiers cannot be decrypted on an unprotected output. The HdcpFallbackSampleApp sample shows how.
* Fixes the video track selection override creator never being applied to a source, which happened when the first track change of that source arrived before a track selection was active.