ash: Add SessionController/Client mojo interfaces

ash/common/session/session_state_delegate.h

 // Copyright 2015 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_STATE_DELEGATE_H_
 #define ASH_COMMON_SESSION_SESSION_STATE_DELEGATE_H_
 
 #include "ash/ash_export.h"
 #include "ash/public/cpp/session_types.h"
 #include "components/session_manager/session_manager_types.h"
 
 class AccountId;
 
 namespace gfx {
 class ImageSkia;
 }
 
 namespace user_manager {
 class UserInfo;
 }
 
 namespace ash {
 
 class SessionStateObserver;
 class WmWindow;
 
 // Delegate for checking and modifying the session state.
+// DEPRECATED in favor of SessionController/SessionControllerClient for mash.
+// TODO(xiyuan): Remove this when SessionController etc are ready.
 class ASH_EXPORT SessionStateDelegate {
  public:
   // Defines the cycle direction for |CycleActiveUser|.
   enum CycleUser {
     CYCLE_TO_NEXT_USER = 0,  // Cycle to the next user.
     CYCLE_TO_PREVIOUS_USER,  // Cycle to the previous user.
   };
 
   virtual ~SessionStateDelegate() {}
 
@@ skipping 62 matching lines @@
   // Adds or removes sessions state observer.
   virtual void AddSessionStateObserver(SessionStateObserver* observer) = 0;
   virtual void RemoveSessionStateObserver(SessionStateObserver* observer) = 0;
 
   bool IsInSecondaryLoginScreen() const;
 };
 
 }  // namespace ash
 
 #endif  // ASH_COMMON_SESSION_SESSION_STATE_DELEGATE_H_