Make the favicons look visually the same after refreshing

ui/gfx/image/image_mac.mm

Index: ui/gfx/image/image_mac.mm
diff --git a/ui/gfx/image/image_mac.mm b/ui/gfx/image/image_mac.mm
index c79100c408592f48e0029fdf13b0c30553aea42d..0158521d007f97cee5f26e454f5987c660192340 100644
--- a/ui/gfx/image/image_mac.mm
+++ b/ui/gfx/image/image_mac.mm
@@ -48,7 +48,8 @@ scoped_refptr<base::RefCountedMemory> Get1xPNGBytesFromNSImage(
   return refcounted_bytes;
 }
 
-NSImage* NSImageFromPNG(const std::vector<gfx::ImagePNGRep>& image_png_reps) {
+NSImage* NSImageFromPNG(const std::vector<gfx::ImagePNGRep>& image_png_reps,
+                        CGColorSpaceRef color_space) {
   if (image_png_reps.empty()) {
     LOG(ERROR) << "Unable to decode PNG.";
     return GetErrorNSImage();
@@ -69,6 +70,23 @@ NSImage* NSImageFromPNG(const std::vector<gfx::ImagePNGRep>& image_png_reps) {
       return GetErrorNSImage();
     }
 
+    // PNGCodec ignores colorspace related ancillary chunks (sRGB, iCCP). Ignore
+    // colorspace information when decoding directly from PNG to an NSImage so
+    // that the conversions: PNG -> SkBitmap -> NSImage and PNG -> NSImage
+    // produce visually similar results.
+    CGColorSpaceModel decoded_color_space_model = CGColorSpaceGetModel(
+        [[ns_image_rep colorSpace] CGColorSpace]);
+    CGColorSpaceModel color_space_model = CGColorSpaceGetModel(color_space);
+    if (decoded_color_space_model == color_space_model) {
+      scoped_nsobject<NSColorSpace> ns_color_space(
+          [[NSColorSpace alloc] initWithCGColorSpace:color_space]);
+      NSBitmapImageRep* ns_retagged_image_rep =
+          [ns_image_rep
+              bitmapImageRepByRetaggingWithColorSpace:ns_color_space];
+      if (ns_retagged_image_rep && ns_retagged_image_rep != ns_image_rep)
+        ns_image_rep.reset([ns_retagged_image_rep retain]);
+    }
+
     if (!image.get()) {
       float scale = ui::GetScaleFactorScale(image_png_reps[i].scale_factor);
       NSSize image_size = NSMakeSize([ns_image_rep pixelsWide] / scale,