Eliminate ash::internal namespace

ash/system/chromeos/session/last_window_closed_logout_reminder.h

 // Copyright 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 ASH_SYSTEM_CHROMEOS_SESSION_LAST_WINDOW_CLOSED_LOGOUT_REMINDER_H_
 #define ASH_SYSTEM_CHROMEOS_SESSION_LAST_WINDOW_CLOSED_LOGOUT_REMINDER_H_
 
 #include "ash/system/chromeos/session/last_window_closed_observer.h"
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 
 namespace ash {
-namespace internal {
 
 // Shows a dialog asking the user whether to end the session when the last
 // window has been closed in a public session.
 class LastWindowClosedLogoutReminder : public LastWindowClosedObserver {
  public:
   LastWindowClosedLogoutReminder();
   virtual ~LastWindowClosedLogoutReminder();
 
   virtual void OnLastWindowClosed() OVERRIDE;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(LastWindowClosedLogoutReminder);
 };
 
-}  // namespace internal
 }  // namespace ash
 
 #endif  // ASH_SYSTEM_CHROMEOS_SESSION_LAST_WINDOW_CLOSED_LOGOUT_REMINDER_H_