Add support for PNG representation in gfx::Image

ui/gfx/image/image.cc

Index: ui/gfx/image/image.cc
diff --git a/ui/gfx/image/image.cc b/ui/gfx/image/image.cc
index c5d30a29210fbf4db294a8f4df3189e27a2c739d..47d0a85aded812efd44c5c790d88cbb614c28683 100644
--- a/ui/gfx/image/image.cc
+++ b/ui/gfx/image/image.cc
@@ -9,6 +9,8 @@
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "third_party/skia/include/core/SkBitmap.h"
+#include "ui/gfx/codec/png_codec.h"
+#include "ui/gfx/image/image_png.h"
 #include "ui/gfx/image/image_skia.h"
 #include "ui/gfx/size.h"
 
@@ -41,6 +43,14 @@ const ImageSkia ImageSkiaFromGdkPixbuf(GdkPixbuf* pixbuf) {
 }
 #endif
 
+const ImageSkia ImageSkiaFromImagePNG(const ImagePNG& png) {
+  SkBitmap bitmap;
+  if (!gfx::PNGCodec::Decode(&png.Image().front(), png.Image().size(), &bitmap))
+    LOG(WARNING) << "Unable to decode PNG, returning empty bitmap";
+  return ImageSkia(bitmap);
+}
+
+class ImageRepPNG;
 class ImageRepSkia;
 class ImageRepGdk;
 class ImageRepCairo;
@@ -59,6 +69,11 @@ class ImageRep {
   virtual ~ImageRep() {}
 
   // Cast helpers ("fake RTTI").
+  ImageRepPNG* AsImageRepPNG() {
+    CHECK_EQ(type_, Image::kImageRepPNG);
+    return reinterpret_cast<ImageRepPNG*>(this);
+  }
+
   ImageRepSkia* AsImageRepSkia() {
     CHECK_EQ(type_, Image::kImageRepSkia);
     return reinterpret_cast<ImageRepSkia*>(this);
@@ -89,6 +104,24 @@ class ImageRep {
   Image::RepresentationType type_;
 };
 
+class ImageRepPNG : public ImageRep {
+ public:
+  explicit ImageRepPNG(const ImagePNG& png)
+      : ImageRep(Image::kImageRepPNG),
+        image_(png) {
+  }
+
+  virtual ~ImageRepPNG() {
+  }
+
+  const ImagePNG& image() const { return image_; }
+
+ private:
+  ImagePNG image_;
+
+  DISALLOW_COPY_AND_ASSIGN(ImageRepPNG);
+};
+
 class ImageRepSkia : public ImageRep {
  public:
   // Takes ownership of |image|.
@@ -219,6 +252,12 @@ Image::Image() {
   // |storage_| is NULL for empty Images.
 }
 
+Image::Image(const ImagePNG& image)
+    : storage_(new internal::ImageStorage(Image::kImageRepPNG)) {
+  internal::ImageRepPNG* rep = new internal::ImageRepPNG(image);
+  AddRepresentation(rep);
+}
+
 Image::Image(const ImageSkia& image)
     : storage_(new internal::ImageStorage(Image::kImageRepSkia)) {
   internal::ImageRepSkia* rep = new internal::ImageRepSkia(
@@ -267,6 +306,35 @@ Image& Image::operator=(const Image& other) {
 Image::~Image() {
 }
 
+const ImagePNG* Image::ToImagePNG() const {
+  internal::ImageRep* rep = GetRepresentation(kImageRepPNG, false);
+  if (!rep) {
+    switch (DefaultRepresentationType()) {
+      // For both native types, ensure that there is an ImageRepSkia and fall
+      // through to that case
+#if defined(TOOLKIT_GTK)
+      case kImageRepGdk:
+        ToImageSkia();
+#elif defined(OS_MACOSX)
+      case kImageRepCocoa:
+        ToImageSkia();
+#endif
+      case kImageRepSkia: {
+        internal::ImageRepSkia* skia_rep =
+          GetRepresentation(kImageRepSkia, true)->AsImageRepSkia();
+        rep = new internal::ImageRepPNG(
+            ImagePNG::FromSkBitmap(skia_rep->image()->bitmap()));
+        break;
+      }
+      default:
+        NOTREACHED();
+    }
+    CHECK(rep);
+    AddRepresentation(rep);
+  }
+  return &rep->AsImageRepPNG()->image();
+}
+
 const SkBitmap* Image::ToSkBitmap() const {
   // Possibly create and cache an intermediate ImageRepSkia.
   return ToImageSkia()->bitmap();
@@ -275,17 +343,34 @@ const SkBitmap* Image::ToSkBitmap() const {
 const ImageSkia* Image::ToImageSkia() const {
   internal::ImageRep* rep = GetRepresentation(kImageRepSkia, false);
   if (!rep) {
+    switch (DefaultRepresentationType()) {
+      case kImageRepPNG: {
+        internal::ImageRepPNG* png_rep =
+          GetRepresentation(kImageRepPNG, true)->AsImageRepPNG();
+        rep = new internal::ImageRepSkia(new ImageSkia(
+            internal::ImageSkiaFromImagePNG(png_rep->image())));
+        break;
+      }
 #if defined(TOOLKIT_GTK)
-    internal::ImageRepGdk* native_rep =
-        GetRepresentation(kImageRepGdk, true)->AsImageRepGdk();
-    rep = new internal::ImageRepSkia(new ImageSkia(
-        internal::ImageSkiaFromGdkPixbuf(native_rep->pixbuf())));
+      case kImageRepGdk: {
+        internal::ImageRepGdk* native_rep =
+            GetRepresentation(kImageRepGdk, true)->AsImageRepGdk();
+        rep = new internal::ImageRepSkia(new ImageSkia(
+            internal::ImageSkiaFromGdkPixbuf(native_rep->pixbuf())));
+        break;
+      }
 #elif defined(OS_MACOSX)
-    internal::ImageRepCocoa* native_rep =
-        GetRepresentation(kImageRepCocoa, true)->AsImageRepCocoa();
-    rep = new internal::ImageRepSkia(new ImageSkia(
-        ImageSkiaFromNSImage(native_rep->image())));
+      case kImageRepCocoa: {
+        internal::ImageRepCocoa* native_rep =
+            GetRepresentation(kImageRepCocoa, true)->AsImageRepCocoa();
+        rep = new internal::ImageRepSkia(new ImageSkia(
+            ImageSkiaFromNSImage(native_rep->image())));
+        break;
+      }
 #endif
+      default:
+        NOTREACHED();
+    }
     CHECK(rep);
     AddRepresentation(rep);
   }
@@ -296,10 +381,20 @@ const ImageSkia* Image::ToImageSkia() const {
 GdkPixbuf* Image::ToGdkPixbuf() const {
   internal::ImageRep* rep = GetRepresentation(kImageRepGdk, false);
   if (!rep) {
-    internal::ImageRepSkia* skia_rep =
-        GetRepresentation(kImageRepSkia, true)->AsImageRepSkia();
-    rep = new internal::ImageRepGdk(gfx::GdkPixbufFromSkBitmap(
-        *skia_rep->image()->bitmap()));
+    switch (DefaultRepresentationType()) {
+      case kImageRepPNG:
+        // Ensure that there is an ImageRepSkia and fall through to that case.
+        ToImageSkia();
+      case kImageRepSkia: {
+        internal::ImageRepSkia* skia_rep =
+            GetRepresentation(kImageRepSkia, true)->AsImageRepSkia();
+        rep = new internal::ImageRepGdk(gfx::GdkPixbufFromSkBitmap(
+            *skia_rep->image()->bitmap()));
+        break;
+      }
+      default:
+        NOTREACHED();
+    }
     CHECK(rep);
     AddRepresentation(rep);
   }
@@ -323,11 +418,21 @@ CairoCachedSurface* const Image::ToCairo() const {
 NSImage* Image::ToNSImage() const {
   internal::ImageRep* rep = GetRepresentation(kImageRepCocoa, false);
   if (!rep) {
-    internal::ImageRepSkia* skia_rep =
-        GetRepresentation(kImageRepSkia, true)->AsImageRepSkia();
-    NSImage* image = NSImageFromImageSkia(*skia_rep->image());
-    base::mac::NSObjectRetain(image);
-    rep = new internal::ImageRepCocoa(image);
+    switch (DefaultRepresentationType()) {
+      case kImageRepPNG:
+        // Ensure that there is a ImageRepSkia and fall through to that case.
+        ToImageSkia();
+      case kImageRepSkia: {
+        internal::ImageRepSkia* skia_rep =
+            GetRepresentation(kImageRepSkia, true)->AsImageRepSkia();
+        NSImage* image = NSImageFromImageSkia(*skia_rep->image());
+        base::mac::NSObjectRetain(image);
+        rep = new internal::ImageRepCocoa(image);
+        break;
+      }
+      default:
+        NOTREACHED();
+    }
     CHECK(rep);
     AddRepresentation(rep);
   }
@@ -335,6 +440,10 @@ NSImage* Image::ToNSImage() const {
 }
 #endif
 
+ImagePNG* Image::CopyImagePNG() const {
+  return new ImagePNG(*ToImagePNG());
+}
+
 ImageSkia* Image::CopyImageSkia() const {
   return new ImageSkia(*ToImageSkia());
 }