Use audio_io_handle_t consistently instead of int

Other:
 - add a comment to nextUniqueId
 - made ThreadBase::mId const, since it is only assigned in constructor.

Change-Id: I4e8b7bec4e45badcde6274d574b8a9aabd046837
10 files changed
tree: beeaffd33a57a6cc5fa48f2fa905fc680c4746d1
  1. camera/
  2. cmds/
  3. drm/
  4. include/
  5. media/
  6. services/