Bluetooth: Mac: implementation for start notification

device/bluetooth/bluetooth_remote_gatt_service_mac.mm

Index: device/bluetooth/bluetooth_remote_gatt_service_mac.mm
diff --git a/device/bluetooth/bluetooth_remote_gatt_service_mac.mm b/device/bluetooth/bluetooth_remote_gatt_service_mac.mm
index aadcf19c9302b7b1350a074d4a1f788b0c97ba76..0d3b7e140d9dce9a48927ce994dc2578866962e2 100644
--- a/device/bluetooth/bluetooth_remote_gatt_service_mac.mm
+++ b/device/bluetooth/bluetooth_remote_gatt_service_mac.mm
@@ -137,6 +137,15 @@ void BluetoothRemoteGattServiceMac::DidWriteValue(
   gatt_characteristic->DidWriteValue(error);
 }
 
+void BluetoothRemoteGattServiceMac::DidUpdateNotificationState(
+    CBCharacteristic* characteristic,
+    NSError* error) {
+  BluetoothRemoteGattCharacteristicMac* gatt_characteristic =
+      GetBluetoothRemoteGattCharacteristicMac(characteristic);
+  DCHECK(gatt_characteristic);
+  gatt_characteristic->DidUpdateNotificationState(error);
+}
+
 bool BluetoothRemoteGattServiceMac::IsDiscoveryComplete() {
   return is_discovery_complete_;
 }