aaudio: implement native IPLayer for legacy playback streams

Make AudioStreamTrack derive from PlayerTrackBase to
provide playback and volume control via IPLayer interface.

Bug: 62027849
Test: verify aaudio playback regressions and registration of aaudio
players in AudioService

Change-Id: I5c04110f1554233eae3f1bc357a64a584d7303d1
8 files changed