Fix wallpaper change to a random one when user first click "set wallpaper".

chrome/browser/chromeos/login/user_manager_impl.h

Index: chrome/browser/chromeos/login/user_manager_impl.h
diff --git a/chrome/browser/chromeos/login/user_manager_impl.h b/chrome/browser/chromeos/login/user_manager_impl.h
index d40688e01f875156f638f365213a0a47004685af..22fab8665347c67a57d3f50ac95beb23c67b27d6 100644
--- a/chrome/browser/chromeos/login/user_manager_impl.h
+++ b/chrome/browser/chromeos/login/user_manager_impl.h
@@ -63,9 +63,8 @@ class UserManagerImpl : public UserManager,
                                     const std::string& display_email) OVERRIDE;
   virtual std::string GetUserDisplayEmail(
       const std::string& username) const OVERRIDE;
-  virtual int GetUserWallpaper(const std::string& username) OVERRIDE;
-  virtual void SaveWallpaperDefaultIndex(const std::string& username,
-                                         int wallpaper_index) OVERRIDE;
+  virtual int GetUserWallpaperIndex() OVERRIDE;
+  virtual void SaveUserWallpaperIndex(int wallpaper_index) OVERRIDE;
   virtual void SaveUserDefaultImageIndex(const std::string& username,
                                          int image_index) OVERRIDE;
   virtual void SaveUserImage(const std::string& username,