Replace scoped_ptr with std::unique_ptr in //ui

ui/views/win/windows_session_change_observer.cc

Index: ui/views/win/windows_session_change_observer.cc
diff --git a/ui/views/win/windows_session_change_observer.cc b/ui/views/win/windows_session_change_observer.cc
index 6d230d6edd073fb6400634f8bd7b3b0312ed7dc1..ddbb3191ae30452d895e4a48a60e8b74c0b68fcd 100644
--- a/ui/views/win/windows_session_change_observer.cc
+++ b/ui/views/win/windows_session_change_observer.cc
@@ -6,13 +6,14 @@
 
 #include <wtsapi32.h>
 
+#include <memory>
+
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/callback.h"
 #include "base/location.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
-#include "base/memory/scoped_ptr.h"
 #include "base/memory/singleton.h"
 #include "base/observer_list.h"
 #include "base/task_runner.h"
@@ -101,7 +102,7 @@ class WindowsSessionChangeObserver::WtsRegistrationNotificationManager {
   }
 
   base::ObserverList<WindowsSessionChangeObserver, true> observer_list_;
-  scoped_ptr<gfx::SingletonHwndObserver> singleton_hwnd_observer_;
+  std::unique_ptr<gfx::SingletonHwndObserver> singleton_hwnd_observer_;
 
   DISALLOW_COPY_AND_ASSIGN(WtsRegistrationNotificationManager);
 };