arc: Implement silent OptIn mode for managed Arc.

chrome/browser/chromeos/arc/arc_android_management_checker.h

Index: chrome/browser/chromeos/arc/arc_android_management_checker.h
diff --git a/chrome/browser/chromeos/arc/arc_android_management_checker.h b/chrome/browser/chromeos/arc/arc_android_management_checker.h
index 3407476862478d197d603de189d21db0c28907e6..9be0db473dfacf5ae8ca80e917f7b7036ae92cf2 100644
--- a/chrome/browser/chromeos/arc/arc_android_management_checker.h
+++ b/chrome/browser/chromeos/arc/arc_android_management_checker.h
@@ -9,7 +9,6 @@
 
 #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"
 
@@ -20,7 +19,7 @@ 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;
 
@@ -38,7 +37,6 @@ class ArcAndroidManagementChecker : public OAuth2TokenService::Observer {
   void DispatchResult(policy::AndroidManagementClient::Result result);
   void OnAndroidManagementChecked(
       policy::AndroidManagementClient::Result result);
-  void OnRefreshTokenTimeout();
 
   // Unowned pointers.
   ArcAndroidManagementCheckerDelegate* const delegate_;
@@ -53,8 +51,6 @@ class ArcAndroidManagementChecker : public OAuth2TokenService::Observer {
   // 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_;