Handle audio route restrictions set on calls

When a call restricts audio routes, it will move the audio route to a
supported route if available. The supported routes are determined initially
and re-evaluated when the call becomes the foreground call.

This is a cherry-pick of abandoned ag/1520954

Bug: 32958838
Change-Id: Ie30847c995839516507df0c70178a591c39f6cdd
5 files changed