SDK / exoplayer

This helps to use the AnalyticsCollector without SimpleExoPlayer. Currently,
that may be problematic, if the contructor needs the player, but in order to
create the player, one already needs the AnalyticsCollector as a listener for
the renderers.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=199105012