Defer focus handling to the content if it claims to have focus.

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 949cdee886780f87be21b0e7f4391a858a2387aa..e9820bedabd33c3dc2905a8615d338eaeae46c5d 100644
--- a/ui/arc/notification/arc_custom_notification_view.h
+++ b/ui/arc/notification/arc_custom_notification_view.h
@@ -62,6 +62,8 @@ class ArcCustomNotificationView
   void OnGestureEvent(ui::GestureEvent* event) override;
   void OnMouseEntered(const ui::MouseEvent& event) override;
   void OnMouseExited(const ui::MouseEvent& event) override;
+  void OnFocus() override;
+  void OnBlur() override;
 
   // views::ButtonListener
   void ButtonPressed(views::Button* sender, const ui::Event& event) override;