Enhance chrome.app.window API for shelf integration with pinning support

chrome/browser/ui/ash/launcher/extension_app_window_launcher_controller.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 CHROME_BROWSER_UI_ASH_LAUNCHER_EXTENSION_APP_WINDOW_LAUNCHER_CONTROLLER_H_
 #define CHROME_BROWSER_UI_ASH_LAUNCHER_EXTENSION_APP_WINDOW_LAUNCHER_CONTROLLER_H_
 
 #include <list>
 #include <map>
 #include <string>
@@ skipping 50 matching lines @@
   // Unregisters a app window with the shelf and this object.
   void UnregisterApp(aura::Window* window);
 
   // Check if a given window is known to the launcher controller.
   bool IsRegisteredApp(aura::Window* window);
 
  private:
   using AppControllerMap =
       std::map<std::string, ExtensionAppWindowLauncherItemController*>;
   using WindowToAppShelfIdMap = std::map<aura::Window*, std::string>;
-  using AppShelfIdToShelfIdMap = std::map<std::string, ash::ShelfID>;
 
   // A set of unowned AppWindowRegistry pointers for loaded users.
   // Note that this will only be used with multiple users in the side by side
   // mode.
   std::set<extensions::AppWindowRegistry*> registry_;
 
   // Map of app launcher id to controller.
   AppControllerMap app_controller_map_;
 
   // Allows us to get from an aura::Window to the app shelf id.
   WindowToAppShelfIdMap window_to_app_shelf_id_map_;
 
-  // Map of app shelf id to shelf id.
-  AppShelfIdToShelfIdMap app_shelf_id_to_shelf_id_map_;
-
   DISALLOW_COPY_AND_ASSIGN(ExtensionAppWindowLauncherController);
 };
 
 #endif  // CHROME_BROWSER_UI_ASH_LAUNCHER_EXTENSION_APP_WINDOW_LAUNCHER_CONTROLLER_H_