Fix IWYU violators that don't include scoped_ptr.h in CrOS build.

chrome/browser/ui/webui/chromeos/login/demo_mode_detector.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 CHROME_BROWSER_UI_WEBUI_CHROMEOS_LOGIN_DEMO_MODE_DETECTOR_H_
 #define CHROME_BROWSER_UI_WEBUI_CHROMEOS_LOGIN_DEMO_MODE_DETECTOR_H_
 
 #include <string>
 
 #include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/time/time.h"
 #include "base/timer/timer.h"
 #include "chrome/browser/chromeos/idle_detector.h"
 
 class PrefRegistrySimple;
 
 namespace chromeos {
 
 // Helper for idle state and demo-mode detection.
@@ skipping 36 matching lines @@
   bool demo_launched_;
 
   base::WeakPtrFactory<DemoModeDetector> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(DemoModeDetector);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_UI_WEBUI_CHROMEOS_LOGIN_DEMO_MODE_DETECTOR_H_