Enhance chrome.app.window API with icon property

ui/gfx/image/image_skia_operations.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 UI_GFX_IMAGE_IMAGE_SKIA_OPERATIONS_H_
 #define UI_GFX_IMAGE_IMAGE_SKIA_OPERATIONS_H_
 
 #include "skia/ext/image_operations.h"
 #include "ui/gfx/color_utils.h"
 #include "ui/gfx/gfx_export.h"
@@ skipping 75 matching lines @@
   // Creates an image with drop shadow defined in |shadows| for |source|.
   static ImageSkia CreateImageWithDropShadow(const ImageSkia& source,
                                              const ShadowValues& shadows);
 
   // Creates an image which is a rotation of the |source|. |rotation| is the
   // amount of clockwise rotation in degrees.
   static ImageSkia CreateRotatedImage(
       const ImageSkia& source,
       SkBitmapOperations::RotationAmount rotation);
 
+  // Creates an icon by painting the second icon as a badge to the first one.
+  // The second icon is in the right corner of the first icon. If the icon
+  // is valid and the badge is not, the icon will be returned. Otherwise, if
+  // the badge is valid and the icon is not, the badge icon will be returned.

[stevenjb, 2016/08/09 16:59:32]

This seems overly complex. An empty |badge| seems reasonable, but if |icon| is
invalid we should just return an empty image.

[Andra Paraschiv, 2016/08/10 14:19:57]

Done.

+  static ImageSkia CreateIconWithBadge(const ImageSkia& icon,
+                                       const ImageSkia& badge);
+
  private:
   ImageSkiaOperations();  // Class for scoping only.
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_IMAGE_IMAGE_SKIA_OPERATIONS_H_