Add UMA for first app list paint on Windows.

chrome/browser/ui/app_list/app_list_service_impl.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_UI_APP_LIST_APP_LIST_SERVICE_IMPL_H_
 #define CHROME_BROWSER_UI_APP_LIST_APP_LIST_SERVICE_IMPL_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 39 matching lines @@
   // app list. Currently this allows for enabling or disabling the app list.
   void HandleCommandLineFlags(Profile* initial_profile);
 
   // Create a platform-specific shortcut for the app list.
   virtual void CreateShortcut();
 
   // Called in response to observed successful and unsuccessful signin changes.
   virtual void OnSigninStatusChanged();
 
   // AppListService overrides:
+  virtual void SetAppListNextPaintCallback(
+      const base::Closure& callback) OVERRIDE;
   virtual void HandleFirstRun() OVERRIDE;
   virtual void Init(Profile* initial_profile) OVERRIDE;
 
   // Returns the app list path configured in BrowserProcess::local_state().
   virtual base::FilePath GetProfilePath(
       const base::FilePath& user_data_dir) OVERRIDE;
   virtual void SetProfilePath(const base::FilePath& profile_path) OVERRIDE;
   virtual void Show() OVERRIDE;
   virtual void EnableAppList(Profile* initial_profile) OVERRIDE;
   virtual AppListControllerDelegate* CreateControllerDelegate() OVERRIDE;
@@ skipping 29 matching lines @@
 
   base::WeakPtrFactory<AppListServiceImpl> weak_factory_;
   content::NotificationRegistrar registrar_;
 
   ProfileLoader profile_loader_;
 
   DISALLOW_COPY_AND_ASSIGN(AppListServiceImpl);
 };
 
 #endif  // CHROME_BROWSER_UI_APP_LIST_APP_LIST_SERVICE_IMPL_H_