SDK / exoplayer

If the same instance is reset then rapidly re-enabling the
renderer after disabling it can prevent an application from
reading the final values at the time when the renderer was
disabled. Hence we now instantiate a new CodecCounters each
time. This is needed to migrate DashTest to V2.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=124721106