Add support for chrome.app.window.create() to app_shell

chrome/browser/apps/chrome_apps_client.h

 // Copyright 2013 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_APPS_CHROME_APPS_CLIENT_H_
 #define CHROME_BROWSER_APPS_CHROME_APPS_CLIENT_H_
 
 #include "apps/apps_client.h"
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 
 template<typename T> struct DefaultSingletonTraits;
 
 // The implementation of AppsClient for Chrome.
 class ChromeAppsClient : public apps::AppsClient {
  public:
   ChromeAppsClient();
   virtual ~ChromeAppsClient();
 
   // Get the LazyInstance for ChromeAppsClient.
   static ChromeAppsClient* GetInstance();
 
  private:
   friend struct DefaultSingletonTraits<ChromeAppsClient>;
 
   // apps::AppsClient
   virtual std::vector<content::BrowserContext*> GetLoadedBrowserContexts()
       OVERRIDE;
-
-  // Do any pre app launch checks. Returns true if the app launch should proceed
-  // or false if the launch should be prevented.
   virtual bool CheckAppLaunch(content::BrowserContext* context,
                               const extensions::Extension* extension) OVERRIDE;
+  virtual apps::AppWindow* CreateAppWindow(
+      content::BrowserContext* context,
+      const extensions::Extension* extension) OVERRIDE;
+  virtual void StartKeepAlive() OVERRIDE;
+  virtual void EndKeepAlive() OVERRIDE;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeAppsClient);
 };
 
 #endif  // CHROME_BROWSER_APPS_CHROME_APPS_CLIENT_H_