olly 3ec0ccabbc Check for null entries in ConcatenatingMediaSource
We do this in the dynamic case, and I think we've seen
a few GitHub issues where developers do this and don't
understand what they've done wrong (because the failure
comes later).

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=163688557
2017-07-31 21:15:42 +01:00
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2017-07-31 20:51:29 +01:00