ash: Add SessionController/Client mojo interfaces

ash/common/session/session_controller.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 ASH_COMMON_SESSION_SESSION_CONTROLLER_H_
+#define ASH_COMMON_SESSION_SESSION_CONTROLLER_H_
+
+#include "ash/public/cpp/session_types.h"
+#include "ash/public/interfaces/session_controller.mojom.h"
+#include "base/macros.h"
+#include "base/observer_list.h"
+#include "mojo/public/cpp/bindings/binding_set.h"
+
+class AccountId;
+
+namespace ash {
+
+class SessionStateObserver;
+
+class SessionController : public mojom::SessionController {

[James Cook, 2016/12/01 23:01:43]

Class comment please

[xiyuan, 2016/12/06 00:46:34]

Done.

+ public:
+  SessionController();
+  ~SessionController() override;
+
+  // Binds the mojom::SessionControllerRequest to this object.
+  void BindRequest(mojom::SessionControllerRequest request);
+
+  // Replacement of SessionStateDelegate interface.

[James Cook, 2016/12/01 23:01:43]

Move or duplicate the SessionStateDelegate function comments here, if this is
going to replace them.

[xiyuan, 2016/12/06 00:46:34]

Done.

+  int GetMaximumNumberOfLoggedInUsers() const;
+  int NumberOfLoggedInUsers() const;
+  AddUserSessionPolicy GetAddUserPolicy() const;
+  bool IsActiveUserSessionStarted() const;
+  bool CanLockScreen() const;
+  bool IsScreenLocked() const;
+  bool ShouldLockScreenAutomatically() const;
+  bool IsUserSessionBlocked() const;
+  session_manager::SessionState GetSessionState() const;
+  const std::vector<mojom::UserSessionPtr>& GetUserSessions() const;
+
+  void LockScreen();

[James Cook, 2016/12/01 23:01:43]

nit: Comment that these mirror or are wrappers around
mojom::SessionControllerClient?

[xiyuan, 2016/12/06 00:46:34]

Copied SessionStateDelegate comments to them.

+  void SwitchActiveUser(const AccountId& account_id);
+  void CycleActiveUser(bool next_user);
+
+  void AddSessionStateObserver(SessionStateObserver* observer);
+  void RemoveSessionStateObserver(SessionStateObserver* observer);
+
+  // mojom::SessionController
+  void SetClient(mojom::SessionControllerClientPtr client) override;
+  void SetMaxUsers(uint32_t max_users) override;
+  void SetCanLockScreen(bool can_lock) override;
+  void SetShouldLockScreenAutomatically(bool should_lock) override;
+  void SetAddUserSessionPolicy(
+      AddUserSessionPolicy add_user_session_policy) override;
+  void SetSessionState(session_manager::SessionState state) override;
+  void SetUserSessions(
+      std::vector<mojom::UserSessionPtr> user_sessions) override;
+
+ private:
+  // Bindings for mojom::SessionController interface.
+  mojo::BindingSet<mojom::SessionController> bindings_;
+
+  // Client interface to Chrome. Only bound on Chrome OS.

[James Cook, 2016/12/01 23:01:43]

nit: remove "Only bound on Chrome OS". I'm in the process of making ash
chromeos-only.

[xiyuan, 2016/12/06 00:46:34]

Done.

+  mojom::SessionControllerClientPtr client_;
+
+  // Cached session info.
+  uint32_t max_users_ = 0u;

[James Cook, 2016/12/01 23:01:43]

#include <stdint.h>

or just use int, I'm not picky about uint/size_t for counts of things

[xiyuan, 2016/12/06 00:46:34]

Done.

+  bool can_lock_ = false;
+  bool should_lock_screen_automatically_ = false;
+  AddUserSessionPolicy add_user_session_policy_ = AddUserSessionPolicy::ALLOWED;
+  session_manager::SessionState state_ = session_manager::SessionState::UNKNOWN;
+  std::vector<mojom::UserSessionPtr> user_sessions_;
+
+  base::ObserverList<ash::SessionStateObserver> observers_;
+
+  DISALLOW_COPY_AND_ASSIGN(SessionController);
+};
+
+}  // namespace ash
+
+#endif  // ASH_COMMON_SESSION_SESSION_CONTROLLER_H_