Refactor extension app icon.

chrome/browser/extensions/extension_app_icon_loader.h

Index: chrome/browser/extensions/extension_app_icon_loader.h
diff --git a/chrome/browser/extensions/extension_app_icon_loader.h b/chrome/browser/extensions/extension_app_icon_loader.h
index e2b4cf914a2dab743d9cf95034c72c044bfce864..9084f9978cd4f7131727061b14bb21b42e1aaca3 100644
--- a/chrome/browser/extensions/extension_app_icon_loader.h
+++ b/chrome/browser/extensions/extension_app_icon_loader.h
@@ -10,8 +10,8 @@
 #include <string>
 
 #include "base/macros.h"
+#include "chrome/browser/extensions/extension_app_icon_delegate.h"
 #include "chrome/browser/ui/app_icon_loader.h"
-#include "extensions/browser/extension_icon_image.h"
 
 class Profile;
 
@@ -20,7 +20,7 @@ namespace extensions {
 // Implementation of AppIconLoader that interacts with the ExtensionService and
 // ImageLoader to load images.
 class ExtensionAppIconLoader : public AppIconLoader,
-                               public extensions::IconImage::Observer {
+                               public ExtensionAppIconDelegate {
  public:
   ExtensionAppIconLoader(Profile* profile, int icon_size,
                          AppIconLoaderDelegate* delegate);
@@ -32,15 +32,12 @@ class ExtensionAppIconLoader : public AppIconLoader,
   void ClearImage(const std::string& id) override;
   void UpdateImage(const std::string& id) override;
 
-  // extensions::IconImage::Observer overrides:
-  void OnExtensionIconImageChanged(extensions::IconImage* image) override;
-
  private:
   using ExtensionIDToImageMap =
-      std::map<std::string, std::unique_ptr<extensions::IconImage>>;
+      std::map<std::string, std::unique_ptr<ExtensionAppIcon>>;
 
-  // Builds image for given |id| and |icon|.
-  void BuildImage(const std::string& id, const gfx::ImageSkia& icon);
+  // ExtensionAppIconDelegate:
+  void OnIconUpdated(ExtensionAppIcon* icon) override;
 
   // Maps from extension id to IconImage pointer.
   ExtensionIDToImageMap map_;