Signal-android: Prevent webrtc and redphone from simultaneously connecting and sharing audio

[riyapenn]

I have:

• [X] searched open and closed issues for duplicates
• [X] read https://github.com/WhisperSystems/Signal-Android/wiki/Submitting-useful-bug-reports

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Bug description

Accepting a redphone call while on a webrtc calls, connects both and enables audio for both calls simultaneously

Steps to reproduce

• place and connect a webrtc call
• receive a redphone call
• accept redphone call

Actual result: Audio is shared with both webrtc call and redphone call; video is still connected to webrtc call
Expected result: Only call displayed on Android screen has audio/video permission; either place other call on hold or display "busy" to caller when receiver is already connected to other call

Screenshots

N/A

Device info

Device: Moto X
Android version: 5.1
Signal version: 3.29.1

Link to debug log

https://gist.github.com/c86609a2156e55c814cb9a031b212bd9

[ZackTS]

Hm, could we introduce group calls this way?