Add isOffloaded method to query AudioTrack offload state.

Use case description

The current interface doesn't provide actual status of offload (whether is enabled on the AudioTrack, not whether it's sleeping). It doesn't allow apps making decisions to keep using offload support after a write error, which may be transient.

Requests:

• call a new method AudioOffloadListener.isOffloadedPlayback with the value of AudioTrack.isOffloadedPlayback. This may be true, even when sleepingForOffload is false.
• Allow AudioOffloadListener to be involved in the DefaultAudioSink maybeDisableOffload decision, such as trying additional times with offload enabled.
• Expose the reason for offload being disabled, such as Audio Init errors, or write errors, or not supported for format.

Proposed solution

Add additional methods to AudioOffloadListener that affect the

Alternatives considered

Expose AudioTrack and additional logging.