Add Builder pattern to ExtractorMediaSource and mark existing constructors as
deprecated.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176088810
- Dropped class name prefixes that correspond to whole app name
- Anything that wraps the player is called PlayerManager
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=173652288