Not Remove Non-Closable Arc Popup When Close Button is Pressed

ui/arc/notification/arc_custom_notification_view.h

Index: ui/arc/notification/arc_custom_notification_view.h
diff --git a/ui/arc/notification/arc_custom_notification_view.h b/ui/arc/notification/arc_custom_notification_view.h
index 7eae0013b453de5336d4f8f8a23691b3f9586bd1..93033d4ff25d331781bb888784efb095fbb16d6c 100644
--- a/ui/arc/notification/arc_custom_notification_view.h
+++ b/ui/arc/notification/arc_custom_notification_view.h
@@ -35,7 +35,7 @@ class ArcCustomNotificationView
       public ArcCustomNotificationItem::Observer,
       public ArcNotificationSurfaceManager::Observer {
  public:
-  explicit ArcCustomNotificationView(ArcCustomNotificationItem* item);
+  ArcCustomNotificationView(ArcCustomNotificationItem* item);
   ~ArcCustomNotificationView() override;
 
   std::unique_ptr<message_center::CustomNotificationContentViewDelegate>
@@ -85,7 +85,7 @@ class ArcCustomNotificationView
   void OnNotificationSurfaceAdded(exo::NotificationSurface* surface) override;
   void OnNotificationSurfaceRemoved(exo::NotificationSurface* surface) override;
 
-  ArcCustomNotificationItem* item_ = nullptr;
+  ArcCustomNotificationItem* item_;
   exo::NotificationSurface* surface_ = nullptr;
 
   const std::string notification_key_;