Handle app custom icon via aura::Window property.

chrome/browser/ui/views/apps/chrome_native_app_window_views.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_UI_VIEWS_APPS_CHROME_NATIVE_APP_WINDOW_VIEWS_H_
 #define CHROME_BROWSER_UI_VIEWS_APPS_CHROME_NATIVE_APP_WINDOW_VIEWS_H_
 
 #include <memory>
 
 #include "base/macros.h"
+#include "chrome/browser/extensions/chrome_app_icon_delegate.h"
 #include "extensions/components/native_app_window/native_app_window_views.h"
 
 class ExtensionKeybindingRegistryViews;
 
 class ChromeNativeAppWindowViews
-    : public native_app_window::NativeAppWindowViews {
+    : public native_app_window::NativeAppWindowViews,
+      public extensions::ChromeAppIconDelegate {
  public:
   ChromeNativeAppWindowViews();
   ~ChromeNativeAppWindowViews() override;
 
   SkRegion* shape() { return shape_.get(); }
 
  protected:
   // Called before views::Widget::Init() in InitializeDefaultWindow() to allow
   // subclasses to customize the InitParams that would be passed.
   virtual void OnBeforeWidgetInit(
@@ skipping 36 matching lines @@
   bool HasFrameColor() const override;
   SkColor ActiveFrameColor() const override;
   SkColor InactiveFrameColor() const override;
 
   // NativeAppWindowViews implementation.
   void InitializeWindow(
       extensions::AppWindow* app_window,
       const extensions::AppWindow::CreateParams& create_params) override;
 
  private:
+  // Ensures that Chrome app icon is created.
+  void EnsureAppIconCreated();
+
+  // extensions::ChromeAppIconDelegate:
+  void OnIconUpdated(extensions::ChromeAppIcon* icon) override;
+
   // Custom shape of the window. If this is not set then the window has a
   // default shape, usually rectangular.
   std::unique_ptr<SkRegion> shape_;
 
   bool has_frame_color_;
   SkColor active_frame_color_;
   SkColor inactive_frame_color_;
   gfx::Size preferred_size_;
 
   // The class that registers for keyboard shortcuts for extension commands.
   std::unique_ptr<ExtensionKeybindingRegistryViews>
       extension_keybinding_registry_;
 
+  // Contains the default Chrome app icon. It is used in case custom icon for
+  // extension app window is not set or as a part of composite image.
+  std::unique_ptr<extensions::ChromeAppIcon> app_icon_;
+
   DISALLOW_COPY_AND_ASSIGN(ChromeNativeAppWindowViews);
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_APPS_CHROME_NATIVE_APP_WINDOW_VIEWS_H_