enable FM tuner and hotword capture for system apps.

AudioRecord constructor with AudioAttributes and session ID as well
as HOTWORD and RADIO_TUNER audio sources are now system APIs.
Renamed MediaRecorder.AudioSource.FM_TUNER to
MediaRecorder.AudioSource.RADIO_TUNER.

Change-Id: I231c20c21e3e8cffe1837482976ebe284c9af541
4 files changed