Revert of Revert of Add CPP API for BLE advertisments.

device/bluetooth/bluetooth_adapter_unittest.cc

Index: device/bluetooth/bluetooth_adapter_unittest.cc
diff --git a/device/bluetooth/bluetooth_adapter_unittest.cc b/device/bluetooth/bluetooth_adapter_unittest.cc
index c028b972218a7fb8ca99476f3674ffc8dc06e391..15a09e12dcb23776171d5796765cb586393e62ad 100644
--- a/device/bluetooth/bluetooth_adapter_unittest.cc
+++ b/device/bluetooth/bluetooth_adapter_unittest.cc
@@ -70,6 +70,11 @@
       const BluetoothAudioSink::Options& options,
       const AcquiredCallback& callback,
       const BluetoothAudioSink::ErrorCallback& error_callback) override {}
+
+  void RegisterAdvertisement(
+      scoped_ptr<BluetoothAdvertisement::Data> advertisement_data,
+      const CreateAdvertisementCallback& callback,
+      const CreateAdvertisementErrorCallback& error_callback) override {}
 
   void TestErrorCallback() {}