arc: Implement silent OptIn mode for managed Arc.

chrome/browser/chromeos/arc/arc_android_management_checker.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_ARC_ANDROID_MANAGEMENT_CHECKER_H_
 #define CHROME_BROWSER_CHROMEOS_ARC_ARC_ANDROID_MANAGEMENT_CHECKER_H_
 
 #include <string>
 
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
-#include "base/timer/timer.h"
 #include "chrome/browser/chromeos/policy/android_management_client.h"
 #include "google_apis/gaia/oauth2_token_service.h"
 
 class ArcAndroidManagementCheckerDelegate;
 class ProfileOAuth2TokenService;
 
 class ArcAndroidManagementChecker : public OAuth2TokenService::Observer {
  public:
   ArcAndroidManagementChecker(ArcAndroidManagementCheckerDelegate* delegate,
                               ProfileOAuth2TokenService* token_service,
-                              const std::string account_id,
+                              const std::string& account_id,
                               bool background_mode);
   ~ArcAndroidManagementChecker() override;
 
   static void StartClient();
 
   // OAuth2TokenService::Observer:
   void OnRefreshTokenAvailable(const std::string& account_id) override;
   void OnRefreshTokensLoaded() override;
 
   bool background_mode() const { return background_mode_; }
 
  private:
   void StartCheck();
   void ScheduleCheck();
   void DispatchResult(policy::AndroidManagementClient::Result result);
   void OnAndroidManagementChecked(
       policy::AndroidManagementClient::Result result);
-  void OnRefreshTokenTimeout();
 
   // Unowned pointers.
   ArcAndroidManagementCheckerDelegate* const delegate_;
   ProfileOAuth2TokenService* const token_service_;
 
   const std::string account_id_;
 
   // In background mode errors are ignored and retry is attempted. There is no
   // retry in foreground mode and result is passed to delegate directly.
   bool background_mode_;
 
   // Keeps current retry time for background mode.
   int retry_time_ms_;
 
-  base::OneShotTimer refresh_token_timeout_;
-
   policy::AndroidManagementClient android_management_client_;
 
   base::WeakPtrFactory<ArcAndroidManagementChecker> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ArcAndroidManagementChecker);
 };
 
 #endif  // CHROME_BROWSER_CHROMEOS_ARC_ARC_ANDROID_MANAGEMENT_CHECKER_H_