Clarify ImageRepSkia constructor arg ownership

Use smart pointers to make the ownership transfer self-documenting.

Change-Id: Ia685023795257c648bfa44637c95e387626ca23a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1503626Reviewed-by: Robert Sesek <rsesek@chromium.org>
Commit-Queue: Florin Malita <fmalita@chromium.org>
Cr-Commit-Position: refs/heads/master@{#638149}

ui/gfx/image/image.cc

@@ -148,11 +148,8 @@ class ImageRepPNG : public ImageRep {
 
 class ImageRepSkia : public ImageRep {
  public:
-  // Takes ownership of |image|.
-  explicit ImageRepSkia(ImageSkia* image)
-      : ImageRep(Image::kImageRepSkia),
-        image_(image) {
-  }
+  explicit ImageRepSkia(std::unique_ptr<ImageSkia> image)
+      : ImageRep(Image::kImageRepSkia), image_(std::move(image)) {}
 
   ~ImageRepSkia() override {}
 
@@ -345,8 +342,8 @@ Image::Image(const std::vector<ImagePNGRep>& image_reps) {
 Image::Image(const ImageSkia& image) {
   if (!image.isNull()) {
     storage_ = new internal::ImageStorage(Image::kImageRepSkia);
-    AddRepresentation(
-        std::make_unique<internal::ImageRepSkia>(new ImageSkia(image)));
+    AddRepresentation(std::make_unique<internal::ImageRepSkia>(
+        std::make_unique<ImageSkia>(image)));
   }
 }
 
@@ -425,16 +422,16 @@ const ImageSkia* Image::ToImageSkia() const {
         const internal::ImageRepCocoaTouch* native_rep =
             GetRepresentation(kImageRepCocoaTouch, true)
                 ->AsImageRepCocoaTouch();
-        scoped_rep.reset(new internal::ImageRepSkia(
-            new ImageSkia(ImageSkiaFromUIImage(native_rep->image()))));
+        scoped_rep.reset(new internal::ImageRepSkia(std::make_unique<ImageSkia>(
+            ImageSkiaFromUIImage(native_rep->image()))));
         break;
       }
 #elif defined(OS_MACOSX)
       case kImageRepCocoa: {
         const internal::ImageRepCocoa* native_rep =
             GetRepresentation(kImageRepCocoa, true)->AsImageRepCocoa();
-        scoped_rep.reset(new internal::ImageRepSkia(
-            new ImageSkia(ImageSkiaFromNSImage(native_rep->image()))));
+        scoped_rep.reset(new internal::ImageRepSkia(std::make_unique<ImageSkia>(
+            ImageSkiaFromNSImage(native_rep->image()))));
         break;
       }
 #endif

ui/gfx/image/image_generic.cc

@@ -4,6 +4,7 @@
 
 #include "ui/gfx/image/image_platform.h"
 
+#include <memory>
 #include <set>
 #include <utility>
 
@@ -16,12 +17,11 @@ namespace internal {
 namespace {
 
 // Returns a 16x16 red image to visually show error in decoding PNG.
-// Caller takes ownership of returned ImageSkia.
-ImageSkia* GetErrorImageSkia() {
+std::unique_ptr<ImageSkia> GetErrorImageSkia() {
   SkBitmap bitmap;
   bitmap.allocN32Pixels(16, 16);
   bitmap.eraseARGB(0xff, 0xff, 0, 0);
-  return new ImageSkia(ImageSkiaRep(bitmap, 1.0f));
+  return std::make_unique<ImageSkia>(ImageSkiaRep(bitmap, 1.0f));
 }
 
 class PNGImageSource : public ImageSkiaSource {
@@ -90,7 +90,8 @@ class PNGImageSource : public ImageSkiaSource {
 
 }  // namespace
 
-ImageSkia* ImageSkiaFromPNG(const std::vector<ImagePNGRep>& image_png_reps) {
+std::unique_ptr<ImageSkia> ImageSkiaFromPNG(
+    const std::vector<ImagePNGRep>& image_png_reps) {
   if (image_png_reps.empty())
     return GetErrorImageSkia();
   std::unique_ptr<PNGImageSource> image_source(new PNGImageSource);
@@ -103,7 +104,7 @@ ImageSkia* ImageSkiaFromPNG(const std::vector<ImagePNGRep>& image_png_reps) {
   DCHECK(!size.IsEmpty());
   if (size.IsEmpty())
     return GetErrorImageSkia();
-  return new ImageSkia(std::move(image_source), size);
+  return std::make_unique<ImageSkia>(std::move(image_source), size);
 }
 
 scoped_refptr<base::RefCountedMemory> Get1xPNGBytesFromImageSkia(

ui/gfx/image/image_ios.mm

@@ -109,11 +109,11 @@ scoped_refptr<base::RefCountedMemory> Get1xPNGBytesFromImageSkia(
   return Get1xPNGBytesFromUIImage(image);
 }
 
-ImageSkia* ImageSkiaFromPNG(
+std::unique_ptr<ImageSkia> ImageSkiaFromPNG(
     const std::vector<gfx::ImagePNGRep>& image_png_reps) {
   // iOS does not expose libpng, so conversion from PNG to ImageSkia must go
   // through UIImage.
-  gfx::ImageSkia* image_skia = new gfx::ImageSkia();
+  auto image_skia = std::make_unique<gfx::ImageSkia>();
   for (size_t i = 0; i < image_png_reps.size(); ++i) {
     base::scoped_nsobject<UIImage> uiimage(
         CreateUIImageFromImagePNGRep(image_png_reps[i]));

ui/gfx/image/image_platform.h

@@ -11,6 +11,7 @@
 #ifndef UI_GFX_IMAGE_IMAGE_PLATFORM_H_
 #define UI_GFX_IMAGE_IMAGE_PLATFORM_H_
 
+#include <memory>
 #include <vector>
 
 #include "base/memory/ref_counted.h"
@@ -45,7 +46,8 @@ NSImage* NSImageFromPNG(const std::vector<ImagePNGRep>& image_png_reps,
 gfx::Size NSImageSize(NSImage* image);
 #endif  // defined(OS_MACOSX)
 
-ImageSkia* ImageSkiaFromPNG(const std::vector<ImagePNGRep>& image_png_reps);
+std::unique_ptr<ImageSkia> ImageSkiaFromPNG(
+    const std::vector<ImagePNGRep>& image_png_reps);
 scoped_refptr<base::RefCountedMemory> Get1xPNGBytesFromImageSkia(
     const ImageSkia* image_skia);