Hearing Aid Service Stub

This is the Hearing Aid service in Java layer.

Bug: 64038649
Test: compilation; toggling the Bluetooth on/off.
Change-Id: Ib32f140d09dd33a9f49ecb91adb8e3cfd5eb3e86
(cherry picked from commit 817f2d076775debd1923c8b4e35c5e47638180a3)
4 files changed