Modal window in user session not blocks user adding screen.

ash/session_state_delegate_stub.h

 // Copyright (c) 2013 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_SESSION_STATE_DELEGATE_STUB_H_
 #define ASH_SESSION_STATE_DELEGATE_STUB_H_
 
 #include "ash/session_state_delegate.h"
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "ui/gfx/image/image_skia.h"
 
 namespace ash {
 
 // Stub implementation of SessionStateDelegate for testing.
 class SessionStateDelegateStub : public SessionStateDelegate {
  public:
   SessionStateDelegateStub();
   virtual ~SessionStateDelegateStub();
 
   // SessionStateDelegate:
   virtual int GetMaximumNumberOfLoggedInUsers() const OVERRIDE;
   virtual int NumberOfLoggedInUsers() const OVERRIDE;
   virtual bool IsActiveUserSessionStarted() const OVERRIDE;
   virtual bool CanLockScreen() const OVERRIDE;
   virtual bool IsScreenLocked() const OVERRIDE;
   virtual void LockScreen() OVERRIDE;
   virtual void UnlockScreen() OVERRIDE;
+  virtual bool IsUserSessionBlocked() const OVERRIDE;
   virtual const base::string16 GetUserDisplayName(
       ash::MultiProfileIndex index) const OVERRIDE;
   virtual const std::string GetUserEmail(
       ash::MultiProfileIndex index) const OVERRIDE;
   virtual const gfx::ImageSkia& GetUserImage(
       ash::MultiProfileIndex index) const OVERRIDE;
   virtual void GetLoggedInUsers(UserIdList* users) OVERRIDE;
   virtual void SwitchActiveUser(const std::string& user_id) OVERRIDE;
   virtual void AddSessionStateObserver(
       ash::SessionStateObserver* observer) OVERRIDE;
   virtual void RemoveSessionStateObserver(
       ash::SessionStateObserver* observer) OVERRIDE;
 
  private:
   bool screen_locked_;
 
   // A pseudo user image.
   gfx::ImageSkia null_image_;
 
   DISALLOW_COPY_AND_ASSIGN(SessionStateDelegateStub);
 };
 
 }  // namespace ash
 
 #endif  // ASH_SESSION_STATE_DELEGATE_STUB_H_