Convert extension action icons code to use ImageSkia instead of SkBitmap

ui/gfx/image/image_skia_operations.cc

Index: ui/gfx/image/image_skia_operations.cc
diff --git a/ui/gfx/image/image_skia_operations.cc b/ui/gfx/image/image_skia_operations.cc
index c4bbce4ac6fa482259dd75f71423fc7e8a427470..97da1bf5a7320d0a14f9634a10f4ae40396c20e9 100644
--- a/ui/gfx/image/image_skia_operations.cc
+++ b/ui/gfx/image/image_skia_operations.cc
@@ -10,6 +10,8 @@
 #include "skia/ext/platform_canvas.h"
 #include "ui/base/layout.h"
 #include "ui/base/ui_base_switches.h"
+#include "ui/gfx/canvas.h"
+#include "ui/gfx/image/canvas_image_source.h"
 #include "ui/gfx/image/image_skia.h"
 #include "ui/gfx/image/image_skia_rep.h"
 #include "ui/gfx/image/image_skia_source.h"
@@ -89,6 +91,33 @@ class BlendingImageSource : public gfx::ImageSkiaSource {
   DISALLOW_COPY_AND_ASSIGN(BlendingImageSource);
 };
 
+class SuperimposedImageSource : public gfx::CanvasImageSource {
+ public:
+  SuperimposedImageSource(const gfx::ImageSkia& first,
+                          const gfx::ImageSkia& second)
+      : gfx::CanvasImageSource(first.size(), false /* is opaque */),
+        first_(first),
+        second_(second) {
+  }
+
+  virtual ~SuperimposedImageSource() {}
+
+  // gfx::CanvasImageSource override.
+  virtual void Draw(gfx::Canvas* canvas) OVERRIDE {
+    canvas->DrawImageInt(first_, 0, 0, SkPaint());
+    canvas->DrawImageInt(second_,
+                         (first_.width() - second_.width()) / 2,
+                         (first_.height() - second_.height()) / 2,
+                         SkPaint());
+  }
+
+ private:
+  const gfx::ImageSkia first_;
+  const gfx::ImageSkia second_;
+
+  DISALLOW_COPY_AND_ASSIGN(SuperimposedImageSource);
+};
+
 class MaskedImageSource : public gfx::ImageSkiaSource {
  public:
   MaskedImageSource(const ImageSkia& rgb, const ImageSkia& alpha)
@@ -322,6 +351,13 @@ ImageSkia ImageSkiaOperations::CreateBlendedImage(const ImageSkia& first,
 }
 
 // static
+ImageSkia ImageSkiaOperations::CreateSuperimposedImage(
+    const ImageSkia& first,
+    const ImageSkia& second) {
+  return ImageSkia(new SuperimposedImageSource(first, second), first.size());
+}
+
+// static
 ImageSkia ImageSkiaOperations::CreateMaskedImage(const ImageSkia& rgb,
                                                  const ImageSkia& alpha) {
   return ImageSkia(new MaskedImageSource(rgb, alpha), rgb.size());