IPrivatePlaybackEventsHandler

Private PlaybackEventsHandler exist for short term work around while TM APIs do not have support for passing in nativeObjects from native side of TM into JS callback.

IPrivatePlaybackEventsHandler interface matches the IPlaybackEventsHandler interface but with the key difference that methods in the private handler do not take a IPlaybackEventsProvider as a parameter and it takes in a providerId to create the JS PlaybackEventsProvider with.