chromeos: Move device shutdown handling out of chrome into ash

chrome/browser/chromeos/settings/shutdown_policy_handler.h

 // Copyright (c) 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_SETTINGS_SHUTDOWN_POLICY_HANDLER_H_
 #define CHROME_BROWSER_CHROMEOS_SETTINGS_SHUTDOWN_POLICY_HANDLER_H_
 
 #include <memory>
 
 #include "base/callback_forward.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 
 namespace chromeos {
 
 // This class observes the device setting |DeviceRebootOnShutdown|. Changes to
 // this policy are communicated to the ShutdownPolicyHandler::Delegate by
 // calling its OnShutdownPolicyChanged method with the new state of the policy.
 class ShutdownPolicyHandler {
  public:
-  // This callback is passed to CheckIfRebootOnShutdown, which invokes it with
-  // the current state of the |DeviceRebootOnShutdown| policy once a trusted of
-  // policies is established.
-  using RebootOnShutdownCallback = base::Callback<void(bool)>;
-
   // This delegate is called when the |DeviceRebootOnShutdown| policy changes.
+  // NotifyDelegateWithShutdownPolicy() can manually request a notification.
   class Delegate {
    public:
     virtual void OnShutdownPolicyChanged(bool reboot_on_shutdown) = 0;
 
    protected:
     virtual ~Delegate() {}
   };
 
   ShutdownPolicyHandler(CrosSettings* cros_settings, Delegate* delegate);
   ~ShutdownPolicyHandler();
 
-  // Once a trusted set of policies is established, this function calls
-  // |callback| with the trusted state of the |DeviceRebootOnShutdown| policy.
-  void CheckIfRebootOnShutdown(const RebootOnShutdownCallback& callback);
-
-  // Resets the policy subscription and clears the delegate.
-  void Shutdown();
+  // Once a trusted set of policies is established, this function notifies
+  // |delegate_| with the trusted state of the |DeviceRebootOnShutdown| policy.
+  void NotifyDelegateWithShutdownPolicy();
 
  private:
-  void CallDelegate(bool reboot_on_shutdown);
-
-  void OnShutdownPolicyChanged();
-
   CrosSettings* cros_settings_;
 
   Delegate* delegate_;
 
   std::unique_ptr<CrosSettings::ObserverSubscription>
       shutdown_policy_subscription_;
 
   base::WeakPtrFactory<ShutdownPolicyHandler> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ShutdownPolicyHandler);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_SETTINGS_SHUTDOWN_POLICY_HANDLER_H_