Extracting more than one wallpaper prominent color

chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.h

 // Copyright 2014 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_CHROMEOS_LOGIN_USERS_WALLPAPER_WALLPAPER_MANAGER_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_USERS_WALLPAPER_WALLPAPER_MANAGER_H_
 
 #include <memory>
 #include <string>
 #include <vector>
 
 #include "ash/public/interfaces/wallpaper.mojom.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted_memory.h"
 #include "base/memory/weak_ptr.h"
 #include "base/scoped_observer.h"
 #include "chrome/browser/chromeos/customization/customization_wallpaper_downloader.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "components/user_manager/user.h"
 #include "components/user_manager/user_image/user_image.h"
 #include "components/user_manager/user_manager.h"
 #include "components/wallpaper/wallpaper_color_calculator.h"
 #include "components/wallpaper/wallpaper_color_calculator_observer.h"
 #include "components/wallpaper/wallpaper_layout.h"
 #include "components/wallpaper/wallpaper_manager_base.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #include "mojo/public/cpp/bindings/binding.h"
 #include "ui/aura/window_observer.h"
-#include "ui/gfx/image/image_skia.h"
 #include "ui/wm/public/activation_change_observer.h"
 #include "ui/wm/public/activation_client.h"
 
+namespace gfx {
+class ImageSkia;
+}
+
 namespace chromeos {
 
 class WallpaperManager
     : public wallpaper::WallpaperManagerBase,
       public ash::mojom::WallpaperPicker,
       public content::NotificationObserver,
       public user_manager::UserManager::UserSessionStateObserver,
       public wm::ActivationChangeObserver,
       public aura::WindowObserver,
       public wallpaper::WallpaperColorCalculatorObserver {
@@ skipping 221 matching lines @@
   std::unique_ptr<wallpaper::WallpaperColorCalculator> color_calculator_;
 
   base::WeakPtrFactory<WallpaperManager> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(WallpaperManager);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_USERS_WALLPAPER_WALLPAPER_MANAGER_H_