MacViews: Use Cocoa folder icons in tree views.

ui/gfx/image/image_skia_operations.cc

 // 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.
 
 #include "ui/gfx/image/image_skia_operations.h"
 
 #include <stddef.h>
 
 #include "base/command_line.h"
 #include "base/logging.h"
@@ skipping 405 matching lines @@
     return ImageSkiaRep(rotated_bitmap, image_rep.scale());
   }
 
  private:
   const ImageSkia source_;
   const SkBitmapOperations::RotationAmount rotation_;
 
   DISALLOW_COPY_AND_ASSIGN(RotatedSource);
 };
 
+// MirroredSource generates image reps that are mirrors of those in |source|.
+class MirroredSource : public ImageSkiaSource {

[tapted, 2016/01/14 23:43:50]

For RTL, another approach is to flip the canvas when drawing rather than
flipping the image asset. See e.g.  ImageButton::OnPaint(gfx::Canvas* canvas) {}

[karandeepb, 2016/01/18 00:31:18]

Done.

+ public:
+  MirroredSource(const ImageSkia& source) : source_(source) {}
+  ~MirroredSource() override {}
+
+  // gfx::ImageSkiaSource overrides:
+  ImageSkiaRep GetImageForScale(float scale) override {
+    const ImageSkiaRep& image_rep = source_.GetRepresentation(scale);
+    const SkBitmap mirrored_bitmap =
+        SkBitmapOperations::CreateMirroredBitmap(image_rep.sk_bitmap());
+    return ImageSkiaRep(mirrored_bitmap, image_rep.scale());
+  }
+
+ private:
+  const ImageSkia source_;
+
+  DISALLOW_COPY_AND_ASSIGN(MirroredSource);
+};
 
 }  // namespace
 
 // static
 ImageSkia ImageSkiaOperations::CreateBlendedImage(const ImageSkia& first,
                                                   const ImageSkia& second,
                                                   double alpha) {
   if (first.isNull() || second.isNull())
     return ImageSkia();
 
@@ skipping 105 matching lines @@
   if (source.isNull())
     return ImageSkia();
 
   return ImageSkia(new RotatedSource(source, rotation),
       SkBitmapOperations::ROTATION_180_CW == rotation ?
           source.size() :
           gfx::Size(source.height(), source.width()));
 
 }
 
+// static
+ImageSkia ImageSkiaOperations::CreateMirroredImage(const ImageSkia& source) {
+  if (source.isNull())
+    return ImageSkia();
+
+  return ImageSkia(new MirroredSource(source), source.size());
+}
+
 }  // namespace gfx