Sync AAudio flowgraph with Oboe

The flowgraph code in AAudio and Oboe should be kept in parity.
The code has diverged and this cl is meant to sync them again.

Bug: 208689965
Test: Build libaaudio/oboeservice and test changes
Change-Id: I1e0cf04120305ffcb1e64df1930ffa079d3c4a94