arc: Show custom notification via notification surface

ui/arc/notification/arc_notification_item.h

Index: ui/arc/notification/arc_notification_item.h
diff --git a/ui/arc/notification/arc_notification_item.h b/ui/arc/notification/arc_notification_item.h
index 3825de03e9e257350bca367568fc5d3085e4b104..deb35133e9c02bdc8b72785a0248c25aab9163aa 100644
--- a/ui/arc/notification/arc_notification_item.h
+++ b/ui/arc/notification/arc_notification_item.h
@@ -13,19 +13,20 @@
 #include "components/signin/core/account_id/account_id.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "ui/arc/notification/arc_notification_manager.h"
+#include "ui/arc/notification/arc_notification_surface_collection.h"
 #include "ui/message_center/message_center.h"
 
 namespace arc {
 
 // The class represents each ARC notification. One instance of this class
 // corresponds to one ARC notification.
-class ArcNotificationItem {
+class ArcNotificationItem : public ArcNotificationSurfaceCollection::Observer {

[yoshiki, 2016/06/15 11:47:20]

Most of ArcNotificationItem code is not shared with custom notification. Could
you create a new class like ArcCurstomNotificationItem which inherits
ArcNotificationItem (or new base class like ArcNotificationItemBase)?

[xiyuan, 2016/06/15 19:32:44]

Done.

  public:
   ArcNotificationItem(ArcNotificationManager* manager,
                       message_center::MessageCenter* message_center,
                       const std::string& notification_key,
                       const AccountId& profile_id);
-  ~ArcNotificationItem();
+  ~ArcNotificationItem() override;
 
   void UpdateWithArcNotificationData(const mojom::ArcNotificationData& data);
 
@@ -38,8 +39,15 @@ class ArcNotificationItem {
   void ButtonClick(int button_index);
 
  private:
+  // ArcNotificationSurfaceCollection::Observer
+  void OnNotificationSurfaceAdded(exo::NotificationSurface* surface) override;
+
   void OnImageDecoded(const SkBitmap& bitmap);
 
+  // Add |notification_| to message center and update again if there is
+  // |newer_data_|.
+  void AddToMessageCenter();
+
   ArcNotificationManager* const manager_;
   message_center::MessageCenter* const message_center_;
   const AccountId profile_id_;