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

ui/arc/notification/arc_custom_notification_item.cc

Index: ui/arc/notification/arc_custom_notification_item.cc
diff --git a/ui/arc/notification/arc_custom_notification_item.cc b/ui/arc/notification/arc_custom_notification_item.cc
index 827e8cb64b0d3606f361e30a20c9d9d220ec3cf9..3779ee1a4c625c87695683ead20e56e6c17e9490 100644
--- a/ui/arc/notification/arc_custom_notification_item.cc
+++ b/ui/arc/notification/arc_custom_notification_item.cc
@@ -25,7 +25,9 @@ constexpr char kNotifierId[] = "ARC_NOTIFICATION";
 class ArcNotificationDelegate : public message_center::NotificationDelegate {
  public:
   explicit ArcNotificationDelegate(ArcCustomNotificationItem* item)
-      : item_(item) {}
+      : item_(item) {
+    DCHECK(item_);
+  }
 
   std::unique_ptr<message_center::CustomContent> CreateCustomContent()
       override {
@@ -35,6 +37,8 @@ class ArcNotificationDelegate : public message_center::NotificationDelegate {
         std::move(view), std::move(content_view_delegate));
   }
 
+  void Close(bool by_user) override { item_->Close(by_user); }
+
  private:
   // The destructor is private since this class is ref-counted.
   ~ArcNotificationDelegate() override {}
@@ -107,13 +111,6 @@ void ArcCustomNotificationItem::UpdateWithArcNotificationData(
   AddToMessageCenter();
 }
 
-void ArcCustomNotificationItem::CloseFromCloseButton() {
-  // Needs to manually remove notification from MessageCenter because
-  // the floating close button is not part of MessageCenter.
-  message_center()->RemoveNotification(notification_id(), true);
-  Close(true);
-}
-
 void ArcCustomNotificationItem::AddObserver(Observer* observer) {
   observers_.AddObserver(observer);
 }