Merge pull request #663 from google/gbg/ancs

Initial support for ANCS client functionality

Merge pull request #650 from google/gbg/gatt-adapter-typing

new GATT adapter classes with proper typing support

Merge pull request #643 from google/gbg/auracast-audio-io

auracast audio io

Merge pull request #641 from zxzxwu/pasync

Receive Periodic Advertising Sync Transfer

Merge pull request #629 from google/gbg/sdp-enforce-mtu

SDP: enforce MTU limits

Merge pull request #598 from google/gbg/gatt-class-adapter

Add a class-based GATT adapter

Merge pull request #599 from google/gbg/hfp-19

add super wide band constants

Merge pull request #583 from google/gbg/more-gatt-tests

regression test for GATT unsubscription

Merge pull request #576 from google/gbg/netsim-device-info

update to new netsim proto with DeviceInfo

Merge pull request #573 from ypomortsev/yegor

HFP: Fix reading multiple AT commands from a single data packet