Dynamic Audio Buffer (1/3)

Add APIs in BluetoothA2dp to:
1. Get the supported type of the dynamic audio buffer.
2. Get the dynamic audio buffer millis.
3. Set dynamic audio buffer millis.

Add BufferConstraints class to access the buffer millis of different
codec.

Bug: 163968696
Tag: #feature
Test: Run dynamic audio buffer test
Change-Id: If097d94be861dbb0c4d8f67fe7caf70a99093e34
4 files changed