Implement //device/bt changes for notifications.

device/bluetooth/dbus/bluetooth_gatt_characteristic_delegate_wrapper.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "device/bluetooth/dbus/bluetooth_gatt_characteristic_delegate_wrapper.h"
 
 #include "device/bluetooth/bluez/bluetooth_local_gatt_characteristic_bluez.h"
 
 namespace bluez {
 
@@ skipping 13 matching lines @@
 
 void BluetoothGattCharacteristicDelegateWrapper::SetValue(
     const std::vector<uint8_t>& value,
     const base::Closure& callback,
     const device::BluetoothLocalGattService::Delegate::ErrorCallback&
         error_callback) {
   service_->GetDelegate()->OnCharacteristicWriteRequest(
       service_, characteristic_, value, 0, callback, error_callback);
 }
 
-void BluetoothGattCharacteristicDelegateWrapper::StartNotifications() {}
+void BluetoothGattCharacteristicDelegateWrapper::StartNotifications() {
+  service_->GetDelegate()->OnNotificationsStart(service_, characteristic_);
+}
 
-void BluetoothGattCharacteristicDelegateWrapper::StopNotifications() {}
+void BluetoothGattCharacteristicDelegateWrapper::StopNotifications() {
+  service_->GetDelegate()->OnNotificationsStop(service_, characteristic_);
+}
 
 }  // namespace bluez