onIsPlayingChanged not called when casting  #9792

Hi I'm trying to implement the cast extension in our app but I'm having some issues with callbacks.

When casting using the ExoPlayer cast extension, pausing and playing the onIsPlayingChanged() callback does not called.

To reproduce

• Add this block of code to the PlayerManager

    @Override
    public void onIsPlayingChanged(boolean isPlaying) {
        if (isPlaying) {
            Log.d("isPlaying","Is playing");
        } else {
            Log.d("isPlaying","Is not playing");
        }
    }

• Load the demo and play some content
• Cast
• Play/Pause content repeatedly

Expected: The onIsPlayingChanged() callback i called with the correct playing state
Actual: The onIsPlayingChanged() is never called

I have noticed onPlayWhenReadyChanged() does get called but we already use onIsPlayingChanged()

• ExoPlayer version number: 2.16.1