Fix race issue in ArcAuthService.

chrome/browser/chromeos/arc/auth/arc_robot_auth.h

-// 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.
-
-#ifndef CHROME_BROWSER_CHROMEOS_ARC_AUTH_ARC_ROBOT_AUTH_H_
-#define CHROME_BROWSER_CHROMEOS_ARC_AUTH_ARC_ROBOT_AUTH_H_
-
-#include <memory>
-
-#include "base/callback.h"
-#include "base/macros.h"
-#include "components/policy/core/common/cloud/device_management_service.h"
-
-namespace arc {
-
-// This class is responsible to fetch auth code for robot account. Robot auth
-// code is used for creation an account on Android side in ARC kiosk mode.
-class ArcRobotAuth {
- public:
-  using RobotAuthCodeCallback = base::Callback<void(const std::string&)>;
-  ArcRobotAuth();
-  ~ArcRobotAuth();
-
-  // Fetches robot auth code. When auth code is fetched, the callback is
-  // invoked. Invoking callback with empty string means a fetch error.
-  // FetchRobotAuthCode() should not be called while another inflight operation
-  // is running.
-  void FetchRobotAuthCode(const RobotAuthCodeCallback& callback);
-
- private:
-  void OnFetchRobotAuthCodeCompleted(
-      RobotAuthCodeCallback callback,
-      policy::DeviceManagementStatus status,
-      int net_error,
-      const enterprise_management::DeviceManagementResponse& response);
-
-  std::unique_ptr<policy::DeviceManagementRequestJob> fetch_request_job_;
-  base::WeakPtrFactory<ArcRobotAuth> weak_ptr_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(ArcRobotAuth);
-};
-
-}  // namespace arc
-
-#endif  // CHROME_BROWSER_CHROMEOS_ARC_AUTH_ARC_ROBOT_AUTH_H_