Don't start FRE from the login screen

chrome/browser/chromeos/login/enrollment/auto_enrollment_controller.h

 // Copyright 2014 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_LOGIN_ENROLLMENT_AUTO_ENROLLMENT_CONTROLLER_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_ENROLLMENT_AUTO_ENROLLMENT_CONTROLLER_H_
 
 #include <memory>
 #include <string>
 #include <vector>
@@ skipping 46 matching lines @@
     EXPLICITLY_NOT_REQUIRED,
   };
 
   // Gets the auto-enrollment mode based on command-line flags and official
   // build status.
   static Mode GetMode();
 
   AutoEnrollmentController();
   ~AutoEnrollmentController();
 
-  // Starts the auto-enrollment check.
+  // Starts the auto-enrollment check.  Safe to call multiple times: aborts in
+  // case a check is currently running or a decision has already been made.
   void Start();
 
-  // Stops any pending auto-enrollment checking.
-  void Cancel();
-
   // Retry checking.
   void Retry();
 
   // Registers a callback to invoke on state changes.
   std::unique_ptr<ProgressCallbackList::Subscription> RegisterProgressCallback(
       const ProgressCallbackList::CallbackType& callback);
 
   policy::AutoEnrollmentState state() const { return state_; }
 
  private:
@@ skipping 50 matching lines @@
   base::WeakPtrFactory<AutoEnrollmentController> client_start_weak_factory_{
       this};
   base::WeakPtrFactory<AutoEnrollmentController> weak_ptr_factory_{this};
 
   DISALLOW_COPY_AND_ASSIGN(AutoEnrollmentController);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_ENROLLMENT_AUTO_ENROLLMENT_CONTROLLER_H_