AndroidAdAudioFocus
Platform AdAudioFocus over AudioManager.
The SDK plays ads on its own ExoPlayer while the content player is paused — and pausing content makes typical integrations (e.g. react-native-theoplayer's AudioFocusManager) abandon the app's focus. Without this, the whole break plays against an EMPTY focus stack: an incoming call cannot pause/duck the ad and other apps' audio mixes over it (PLAYG-458). Holding AUDIOFOCUS_GAIN with USAGE_MEDIA for the duration of the break restores normal system focus semantics to ad playback.