Notify about major session changes events.

chrome/browser/ui/ash/session_state_delegate_chromeos.h

Index: chrome/browser/ui/ash/session_state_delegate_chromeos.h
diff --git a/chrome/browser/ui/ash/session_state_delegate_chromeos.h b/chrome/browser/ui/ash/session_state_delegate_chromeos.h
index b6dc92222507f21fb9abf4b7b27a8c72529ffaf1..541c6d38829dd8353849c66ead774f36e1a24b75 100644
--- a/chrome/browser/ui/ash/session_state_delegate_chromeos.h
+++ b/chrome/browser/ui/ash/session_state_delegate_chromeos.h
@@ -9,6 +9,7 @@
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/observer_list.h"
+#include "chrome/browser/chromeos/login/user_adding_screen.h"
 #include "chrome/browser/chromeos/login/user_manager.h"
 
 namespace ash {
@@ -17,7 +18,8 @@ class SessionStateObserver;
 
 class SessionStateDelegateChromeos
     : public ash::SessionStateDelegate,
-      public chromeos::UserManager::UserSessionStateObserver {
+      public chromeos::UserManager::UserSessionStateObserver,
+      public chromeos::UserAddingScreen::Observer {
  public:
   SessionStateDelegateChromeos();
   virtual ~SessionStateDelegateChromeos();
@@ -51,14 +53,27 @@ class SessionStateDelegateChromeos
       ash::SessionStateObserver* observer) OVERRIDE;
   virtual void RemoveSessionStateObserver(
       ash::SessionStateObserver* observer) OVERRIDE;
+
   // UserManager::UserSessionStateObserver:
   virtual void ActiveUserChanged(const chromeos::User* active_user) OVERRIDE;
   virtual void UserAddedToSession(const chromeos::User* added_user) OVERRIDE;
 
+  // UserAddingScreen::Observer:
+  virtual void OnUserAddingStarted() OVERRIDE;
+  virtual void OnUserAddingFinished() OVERRIDE;
+
  private:
+  // Sets session state to |new_state|.
+  void SetSessionState(SessionState new_state);
+
+  // Notify observers about session state change.
+  void NotifySessionStateChanged();
+
   // List of observers is only used on Chrome OS for now.
   ObserverList<ash::SessionStateObserver> session_state_observer_list_;
 
+  SessionState state_;
+
   DISALLOW_COPY_AND_ASSIGN(SessionStateDelegateChromeos);
 };