Fix the crash in DesktopBackgroundView::OnPaint

chrome/browser/chromeos/login/wallpaper_manager.h

Index: chrome/browser/chromeos/login/wallpaper_manager.h
diff --git a/chrome/browser/chromeos/login/wallpaper_manager.h b/chrome/browser/chromeos/login/wallpaper_manager.h
index fd7bb8876f144876c8db62507975849df967bbab..57c8a8102352094214a7e48e055b64406d808091 100644
--- a/chrome/browser/chromeos/login/wallpaper_manager.h
+++ b/chrome/browser/chromeos/login/wallpaper_manager.h
@@ -206,7 +206,7 @@ class WallpaperManager: public system::TimezoneSettings::Observer,
 
   // Generates a 128x80 thumbnail and caches it.
   void CacheThumbnail(const std::string& email,
-                      const gfx::ImageSkia& wallpaper);
+                      scoped_ptr<gfx::ImageSkia> wallpaper);
 
   // Deletes a list of wallpaper files in |file_list|.
   void DeleteWallpaperInList(const std::vector<FilePath>& file_list);
@@ -265,6 +265,15 @@ class WallpaperManager: public system::TimezoneSettings::Observer,
   void OnWallpaperEncoded(const FilePath& path,
                           scoped_refptr<base::RefCountedBytes> data);
 
+  // Generates thumbnail of custom wallpaper on FILE thread. If |persistent| is
+  // true, saves original custom image and resized images to disk.
+  void ProcessCustomWallpaper(const std::string& email,
+                              bool persistent,
+                              const WallpaperInfo& info,
+                              base::WeakPtr<WallpaperDelegate> delegate,
+                              scoped_ptr<gfx::ImageSkia> image,
+                              const UserImage::RawImage& raw_image);
+
   // Record data for User Metrics Analysis.
   void RecordUma(User::WallpaperType type, int index);