Add unittests of ArcCustomNotificationView

ui/arc/notification/arc_notification_surface_manager.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef UI_ARC_NOTIFICATION_ARC_NOTIFICATION_SURFACE_MANAGER_
-#define UI_ARC_NOTIFICATION_ARC_NOTIFICATION_SURFACE_MANAGER_
+#ifndef UI_ARC_NOTIFICATION_ARC_NOTIFICATION_SURFACE_MANAGER_H_
+#define UI_ARC_NOTIFICATION_ARC_NOTIFICATION_SURFACE_MANAGER_H_
 
 #include <map>
 #include <string>
 
 #include "base/macros.h"
 #include "base/observer_list.h"
 #include "components/exo/notification_surface_manager.h"
 
 namespace arc {
 
+class ArcNotificationSurface;
+
 // Keeps track of NotificationSurface.
-class ArcNotificationSurfaceManager : public exo::NotificationSurfaceManager {
+class ArcNotificationSurfaceManager {
  public:
   class Observer {
    public:
     // Invoked when a notification surface is added to the registry.
     virtual void OnNotificationSurfaceAdded(
-        exo::NotificationSurface* surface) = 0;
+        ArcNotificationSurface* surface) = 0;
 
     // Invoked when a notification surface is removed from the registry.
     virtual void OnNotificationSurfaceRemoved(
-        exo::NotificationSurface* surface) = 0;
+        ArcNotificationSurface* surface) = 0;
 
    protected:
     virtual ~Observer() = default;
   };
 
   ArcNotificationSurfaceManager();
-  ~ArcNotificationSurfaceManager() override;
+  ~ArcNotificationSurfaceManager();
 
   static ArcNotificationSurfaceManager* Get();
 
-  // exo::NotificationSurfaceManager:
-  exo::NotificationSurface* GetSurface(
-      const std::string& notification_id) const override;
-  void AddSurface(exo::NotificationSurface* surface) override;
-  void RemoveSurface(exo::NotificationSurface* surface) override;
+  virtual ArcNotificationSurface* GetArcSurface(
+      const std::string& notification_id) const = 0;
 
-  void AddObserver(Observer* observer);
-  void RemoveObserver(Observer* observer);
+  virtual void AddObserver(Observer* observer) = 0;
+  virtual void RemoveObserver(Observer* observer) = 0;
 
  private:
-  using NotificationSurfaceMap =
-      std::map<std::string, exo::NotificationSurface*>;
-  NotificationSurfaceMap notification_surface_map_;
-
-  base::ObserverList<Observer> observers_;
+  static ArcNotificationSurfaceManager* instance_;
 
   DISALLOW_COPY_AND_ASSIGN(ArcNotificationSurfaceManager);
 };
 
 }  // namespace arc
 
-#endif  // UI_ARC_NOTIFICATION_ARC_NOTIFICATION_SURFACE_MANAGER_
+#endif  // UI_ARC_NOTIFICATION_ARC_NOTIFICATION_SURFACE_MANAGER_H_