Changes to default apps promo per ui leads:

chrome/browser/dom_ui/app_launcher_handler.h

 // Copyright (c) 2010 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_DOM_UI_APP_LAUNCHER_HANDLER_H_
 #define CHROME_BROWSER_DOM_UI_APP_LAUNCHER_HANDLER_H_
 #pragma once
 
 #include "base/scoped_ptr.h"
 #include "chrome/browser/dom_ui/dom_ui.h"
 #include "chrome/browser/extensions/extension_install_ui.h"
 #include "chrome/browser/prefs/pref_change_registrar.h"
 #include "chrome/common/notification_observer.h"
 #include "chrome/common/notification_registrar.h"
 
 class Extension;
 class ExtensionPrefs;
 class ExtensionService;
 class NotificationRegistrar;
 class PrefChangeRegistrar;
+class Profile;
 
 namespace gfx {
   class Rect;
 }
 
 // The handler for Javascript messages related to the "apps" view.
 class AppLauncherHandler
     : public DOMMessageHandler,
       public ExtensionInstallUI::Delegate,
       public NotificationObserver {
  public:
   explicit AppLauncherHandler(ExtensionService* extension_service);
   virtual ~AppLauncherHandler();
 
   // Populate a dictionary with the information from an extension.
   static void CreateAppInfo(const Extension* extension,
                             ExtensionPrefs* extension_prefs,
                             DictionaryValue* value);
 
   // Callback for pings related to launching apps on the NTP.
-  static bool HandlePing(const std::string& path);
+  static bool HandlePing(Profile* profile, const std::string& path);
 
   // DOMMessageHandler implementation.
   virtual DOMMessageHandler* Attach(DOMUI* dom_ui);
   virtual void RegisterMessages();
 
   // NotificationObserver
   virtual void Observe(NotificationType type,
                       const NotificationSource& source,
                       const NotificationDetails& details);
 
@@ skipping 32 matching lines @@
   virtual void InstallUIProceed();
   virtual void InstallUIAbort();
 
   // Returns the ExtensionInstallUI object for this class, creating it if
   // needed.
   ExtensionInstallUI* GetExtensionInstallUI();
 
   // Starts the animation of the app icon.
   void AnimateAppIcon(const Extension* extension, const gfx::Rect& rect);
 
+  // Helper that uninstalls all the default apps.
+  void UninstallDefaultApps();
+
   // The apps are represented in the extensions model.
   scoped_refptr<ExtensionService> extensions_service_;
 
   // We monitor changes to the extension system so that we can reload the apps
   // when necessary.
   NotificationRegistrar registrar_;
 
   // Monitor extension preference changes so that the DOM UI can be notified.
   PrefChangeRegistrar pref_change_registrar_;
 
   // Used to show confirmation UI for uninstalling/enabling extensions in
   // incognito mode.
   scoped_ptr<ExtensionInstallUI> install_ui_;
 
   // The id of the extension we are prompting the user about.
   std::string extension_id_prompting_;
 
   // Whether the promo is currently being shown.
   bool promo_active_;
 
+  // When true, we ignore changes to the underlying data rather than immediately
+  // refreshing. This is useful when making many batch updates to avoid flicker.
+  bool ignore_changes_;
+
   DISALLOW_COPY_AND_ASSIGN(AppLauncherHandler);
 };
 
 #endif  // CHROME_BROWSER_DOM_UI_APP_LAUNCHER_HANDLER_H_