This is the first step towards facilitating Cast integration to ExoPlayer.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=162366198
This is possible to do without passing the player instance to
custom action providers through their constructors, given we
no longer have a MuteActionProvider. Passing the player through
the constructors generalizes better to such cases, however, so
feels like the right thing to do.
It's also possible to use generics and keep passing the player
instance via the CustomActionProvider methods, but this adds
some unnecessary complexity.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=162333043