[CrOS Tether] Create TetherDisconnector, which disconnects from active tethering sessions.

chromeos/components/tether/disconnect_tethering_operation.cc

 // Copyright 2017 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 "chromeos/components/tether/disconnect_tethering_operation.h"
 
 #include "chromeos/components/tether/message_wrapper.h"
 #include "chromeos/components/tether/proto/tether.pb.h"
 #include "components/proximity_auth/logging/logging.h"
 
@@ skipping 30 matching lines @@
   return base::MakeUnique<DisconnectTetheringOperation>(device_to_connect,
                                                         connection_manager);
 }
 
 DisconnectTetheringOperation::DisconnectTetheringOperation(
     const cryptauth::RemoteDevice& device_to_connect,
     BleConnectionManager* connection_manager)
     : MessageTransferOperation(
           std::vector<cryptauth::RemoteDevice>{device_to_connect},
           connection_manager),
+      device_id_(device_to_connect.GetDeviceId()),
       has_authenticated_(false) {}
 
 DisconnectTetheringOperation::~DisconnectTetheringOperation() {}
 
 void DisconnectTetheringOperation::AddObserver(Observer* observer) {
   observer_list_.AddObserver(observer);
 }
 
 void DisconnectTetheringOperation::RemoveObserver(Observer* observer) {
   observer_list_.RemoveObserver(observer);
 }
 
+void DisconnectTetheringOperation::NotifyObserversOperationFinished(
+    bool success) {
+  for (auto& observer : observer_list_) {
+    observer.OnOperationFinished(device_id_, success);
+  }
+}
+
 void DisconnectTetheringOperation::OnDeviceAuthenticated(
     const cryptauth::RemoteDevice& remote_device) {
   DCHECK(remote_devices().size() == 1u && remote_devices()[0] == remote_device);
   has_authenticated_ = true;
 
   SendMessageToDevice(remote_device, base::MakeUnique<MessageWrapper>(
                                          DisconnectTetheringRequest()));
   UnregisterDevice(remote_device);
 }
 
 void DisconnectTetheringOperation::OnOperationFinished() {
-  for (auto& observer : observer_list_) {
-    observer.OnOperationFinished(has_authenticated_);
-  }
+  NotifyObserversOperationFinished(has_authenticated_);
 }
 
 MessageType DisconnectTetheringOperation::GetMessageTypeForConnection() {
   return MessageType::DISCONNECT_TETHERING_REQUEST;
 }
 
 }  // namespace tether
 
 }  // namespace chromeos