Convert //ash from scoped_ptr to std::unique_ptr

ash/system/tray/system_tray_unittest.cc

Index: ash/system/tray/system_tray_unittest.cc
diff --git a/ash/system/tray/system_tray_unittest.cc b/ash/system/tray/system_tray_unittest.cc
index c61776ef62679345686e42f1e43ce401875cc47c..30c2b120defbbe5b867e04906cad37cbf94f8f77 100644
--- a/ash/system/tray/system_tray_unittest.cc
+++ b/ash/system/tray/system_tray_unittest.cc
@@ -391,7 +391,7 @@ TEST_F(SystemTrayTest, PersistentBubble) {
   TestItem* test_item = new TestItem;
   tray->AddTrayItem(test_item);
 
-  scoped_ptr<aura::Window> window(CreateTestWindowInShellWithId(0));
+  std::unique_ptr<aura::Window> window(CreateTestWindowInShellWithId(0));
 
   // Tests for usual default view.
   // Activating window.
@@ -477,7 +477,7 @@ TEST_F(SystemTrayTest, SetVisibleDuringHideAnimation) {
   SystemTray* tray = GetSystemTray();
   ASSERT_TRUE(tray->visible());
 
-  scoped_ptr<ui::ScopedAnimationDurationScaleMode> animation_duration;
+  std::unique_ptr<ui::ScopedAnimationDurationScaleMode> animation_duration;
   animation_duration.reset(
       new ui::ScopedAnimationDurationScaleMode(
           ui::ScopedAnimationDurationScaleMode::SLOW_DURATION));