SDK / exoplayer

As part of this change:

- Don't apply the workaround on API level 27+. GTS coverage
  should prevent such devices from existing.
- Use Util.DEVICE consistently.
- Remove the "// Device name", which don't really add much
  but make extra work when updating the list.

Issue: #4468

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=204889657