b69ffd4dc2
This is the minimum change to make adjusting volume work with MediaSessions. This only affects adjusting the volume and adjusting the volume with a suggested stream. Adjusting a specific stream or setting a specific stream will still use the same code. This does not fix existing remote volume handling in RCC, which will require a separate change to MediaController. Change-Id: I5b957ff4bece1ee11e2364e1f216e1c08343c983