Show/Hide the Arc App windows and corresponding shelf items when switching between desktops.

chrome/browser/ui/ash/launcher/arc_app_window_launcher_controller.h

Index: chrome/browser/ui/ash/launcher/arc_app_window_launcher_controller.h
diff --git a/chrome/browser/ui/ash/launcher/arc_app_window_launcher_controller.h b/chrome/browser/ui/ash/launcher/arc_app_window_launcher_controller.h
index 76e7cb99aa301eb533df269b0921e43309294bd3..64889d15fd329042dfd22b2d0b589c07ee2758b5 100644
--- a/chrome/browser/ui/ash/launcher/arc_app_window_launcher_controller.h
+++ b/chrome/browser/ui/ash/launcher/arc_app_window_launcher_controller.h
@@ -63,10 +63,6 @@ class ArcAppWindowLauncherController : public AppWindowLauncherController,
   void OnTaskDestroyed(int task_id) override;
   void OnTaskSetActive(int32_t task_id) override;
 
- protected:
-  void StartObserving(Profile* profile);
-  void StopObserving(Profile* profile);
-
  private:
   class AppWindow;
 
@@ -74,6 +70,12 @@ class ArcAppWindowLauncherController : public AppWindowLauncherController,
   using AppControllerMap =
       std::map<std::string, ArcAppWindowLauncherItemController*>;
 
+  void StartObserving(Profile* profile);
+  void StopObserving(Profile* profile);
+
+  void RegisterApp(AppWindow* app_window);
+  void UnregisterApp(AppWindow* app_window);
+
   AppWindow* GetAppWindowForTask(int task_id);
 
   void CheckForAppWindowWidget(aura::Window* window);