[ash-md] Wired in the Shelf color to be derived from the Wallpaper.

ash/common/wallpaper/wallpaper_controller.h

 // Copyright (c) 2012 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 ASH_COMMON_WALLPAPER_WALLPAPER_CONTROLLER_H_
 #define ASH_COMMON_WALLPAPER_WALLPAPER_CONTROLLER_H_
 
 #include <memory>
 
 #include "ash/ash_export.h"
 #include "ash/common/shell_observer.h"
 #include "ash/common/wm_display_observer.h"
 #include "ash/public/interfaces/wallpaper.mojom.h"
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
 #include "base/observer_list.h"
 #include "base/timer/timer.h"
+#include "components/wallpaper/wallpaper_color_calculator_observer.h"
 #include "components/wallpaper/wallpaper_layout.h"
+#include "components/wallpaper/wallpaper_resizer_observer.h"
 #include "mojo/public/cpp/bindings/binding_set.h"
+#include "ui/gfx/color_analysis.h"
 #include "ui/gfx/image/image_skia.h"
 
 namespace base {
 class TaskRunner;
 }
 
 namespace wallpaper {
+class WallpaperColorCalculator;
 class WallpaperResizer;
 }
 
 namespace ash {
 
 class WallpaperControllerObserver;
 
 // Controls the desktop background wallpaper.
 class ASH_EXPORT WallpaperController
     : public NON_EXPORTED_BASE(mojom::WallpaperController),
       public WmDisplayObserver,
-      public ShellObserver {
+      public ShellObserver,
+      public wallpaper::WallpaperResizerObserver,
+      public wallpaper::WallpaperColorCalculatorObserver {
  public:
   enum WallpaperMode { WALLPAPER_NONE, WALLPAPER_IMAGE };
 
   explicit WallpaperController(
       const scoped_refptr<base::TaskRunner>& task_runner);
   ~WallpaperController() override;
 
   // Binds the mojom::WallpaperController interface request to this object.
   void BindRequest(mojom::WallpaperControllerRequest request);
 
   // Add/Remove observers.
   void AddObserver(WallpaperControllerObserver* observer);
   void RemoveObserver(WallpaperControllerObserver* observer);
 
+  SkColor prominent_color() const { return prominent_color_; }
+
   // Provides current image on the wallpaper, or empty gfx::ImageSkia if there
   // is no image, e.g. wallpaper is none.
   gfx::ImageSkia GetWallpaper() const;
 
   wallpaper::WallpaperLayout GetWallpaperLayout() const;
 
   // Sets the wallpaper and alerts observers of changes.
   void SetWallpaperImage(const gfx::ImageSkia& image,
                          wallpaper::WallpaperLayout layout);
 
@@ skipping 37 matching lines @@
   }
 
   // Opens the set wallpaper page in the browser.
   void OpenSetWallpaperPage();
 
   // mojom::WallpaperController overrides:
   void SetWallpaperPicker(mojom::WallpaperPickerPtr picker) override;
   void SetWallpaper(const SkBitmap& wallpaper,
                     wallpaper::WallpaperLayout layout) override;
 
+  // WallpaperResizerObserver:
+  void OnWallpaperResized() override;
+
+  // WallpaperColorCalculatorObserver:
+  void OnColorCalculationComplete() override;
+
  private:
+  // Returns true if the shelf should be colored based on the wallpaper's
+  // prominent color. |luma| and |saturation| are output parameters.
+  static bool GetProminentColorProfile(
+      color_utils::LumaRange* luma,
+      color_utils::SaturationRange* saturation);
+
   // Creates a WallpaperWidgetController for |root_window|.
   void InstallDesktopController(WmWindow* root_window);
 
   // Creates a WallpaperWidgetController for all root windows.
   void InstallDesktopControllerForAllWindows();
 
   // Moves the wallpaper to the specified container across all root windows.
   // Returns true if a wallpaper moved.
   bool ReparentWallpaper(int container);
 
   // Returns the wallpaper container id for unlocked and locked states.
   int GetWallpaperContainerId(bool locked);
 
   // Reload the wallpaper. |clear_cache| specifies whether to clear the
   // wallpaper cahce or not.
   void UpdateWallpaper(bool clear_cache);
 
+  // Sets |prominent_color_| and notifies the observers if there is a change.
+  void SetProminentColor(SkColor color);
+
+  // If enabled, will initiates an asynchronous task to extract colors from the
+  // wallpaper. If an existing calculation is in progress it is destroyed.
+  void CalculateWallpaperColors();
+
   bool locked_;
 
   WallpaperMode wallpaper_mode_;
 
   // Wallpaper picker interface in chrome browser, used to open the picker.
   mojom::WallpaperPickerPtr wallpaper_picker_;
 
   // Bindings for the WallpaperController interface.
   mojo::BindingSet<mojom::WallpaperController> bindings_;
 
   base::ObserverList<WallpaperControllerObserver> observers_;
 
   std::unique_ptr<wallpaper::WallpaperResizer> current_wallpaper_;
 
+  // Asynchronous task to extract colors from the wallpaper.
+  std::unique_ptr<wallpaper::WallpaperColorCalculator> color_calculator_;
+
+  // The prominent color extracted from the current wallpaper.
+  // SK_ColorTRANSPARENT is used by default or if extracting colors fails.
+  SkColor prominent_color_;
+
   gfx::Size current_max_display_size_;
 
   base::OneShotTimer timer_;
 
   int wallpaper_reload_delay_;
 
   scoped_refptr<base::TaskRunner> task_runner_;
 
   DISALLOW_COPY_AND_ASSIGN(WallpaperController);
 };
 
 }  // namespace ash
 
 #endif  // ASH_COMMON_WALLPAPER_WALLPAPER_CONTROLLER_H_