GitLab

Implement BleAdapterPowerManager that handles
1) Observing BluetoothAdapter for power state change and notifying
FidoRequestHandlerBase::TransportAvailabilityObserver.
2) If BluetoothAdapter has been powered on programmatically, turning off
bluetooth adapter power on destructor.
3) Exposing API to FidoRequestHandlerBase to power on bluetooth adapter.

TBR: jam@chromium.org
Bug: 877344
Change-Id: I3a99782186e232f1242937867c5091a4ee1ec338
Reviewed-on: https://chromium-review.googlesource.com/1195150
Commit-Queue: Jun Choi <hongjunchoi@chromium.org>
Reviewed-by: Balazs Engedy <engedy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#587475}