SDK / exoplayer

The default character set is always UTF-8 anyway on Android, but
we don't want our code to behave any differently where it's not
(e.g. robolectric test runs could potentially run in an environment
where UTF-8 isn't the default?).

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=211953885