tonihei 5ce2f1763d Check if source has been prepared before releasing it.
In ConcatenatingMediaSource, the source may be removed before it started
preparing (this may happen if lazyPreparation=true). In this case, we
shouldn't call releaseSource as the preparation didn't start.

Issue:#4986

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=218141658
2018-10-24 18:30:51 +01:00
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2018-10-18 23:17:16 +01:00