AudioFlinger: Add Track interfaces

Add new interfaces

IAfTrackBase
IAfTrack
IAfOutputTrack
IAfMmapTrack
IAfRecordTrack

Test: atest audiorecord_tests audiotrack_tests audiorouting_tests trackplayerbase_tests audiosystem_tests
Test: atest AudioTrackTest AudioRecordTest
Test: YouTube Camera
Bug: 288339104
Bug: 288468076
Merged-In: Iee8fd68fcd1c430da09b11d68a57fc62ba4c6f75
Change-Id: Iee8fd68fcd1c430da09b11d68a57fc62ba4c6f75
(cherry picked from commit d29af631)