Audio stream is not stopped at hmi level none and background

[t-yoshii]

Bug Report

Audio stream is not stopped when hmi level are changed to none or background from limited or full.
According to this guide, audio streaming is only allowed at hmi level limited and full.
https://smartdevicelink.com/en/guides/iOS/mobile-navigation/audio-streaming/

Reproduction Steps

1. Start SDL app (appHMIType = Navigation) and connect to SDL core
2. Change HMI level to full
3. Change HMI level to background or none

Expected Behavior

Audio streaming and video streaming are stopped

Observed Behavior

Audio streaming is not stopped. Only video streaming is stopped.

OS & Version Information

• iOS Version: 11.1.2
• SDL iOS Version: 5.0.0-rc3
• Testing Against: Our in-house testing SDL HMI devboard

Test Case, Sample Code, and / or Example App

PR will be created.

[joeljfischer]

This does not seem to have been fixed in the AudioStreamManager