AudioTrack API for delay/padding in offload

Add API to add support for specifying delay and padding values
  for the current compressed stream.
Add API to indicate the end of stream after a write() operation

Bug: 122825812
Test: atest AudioTrackOffloadTest
Change-Id: Ib4dc76938fb5cea77ce67aa12aca7d38f66e756c
4 files changed