Add mute button during calls and videocalls on TV

I was on a videocall and I noticed I was unable to mute it so I had to hang up in order to say something that I didn't want the other party to hear.

changed title from [Feature Request] Add mute button during calls and videocalls on Android TV to [Feature Request] Add mute button during calls and videocalls on TV UI

changed title from [Feature Request] Add mute button during calls and videocalls on TV UI to Add mute button during calls and videocalls on TV

added androidtv BacklogMedium + 1 deleted label

added typefeature request label

mentioned in issue #1859