Respect SkColorSpace in SkPNGImageEncoder

This only changes behavior when the input SkBitmap/SkPixmap is
tagged with a non-null SkColorSpace.  Android tags their bitmaps
as sRGB when linear blending is enabled.  So this only changes
behavior in Android when linear blending is turned on.
*If linear blending is turned on, this will do a color correct
 encode (which is the desired behavior).
*If linear blending is turned off, this will do a legacy encode.

TODO: Add support for F16.
TODO: Add color space support to WEBP.
TODO: Tag encoded images with ICC profiles (when it makes sense).

BUG=skia:

Change-Id: Idd8a2836371d24a453d953e6fe2e76a87751be96
Reviewed-on: https://skia-review.googlesource.com/6498
Reviewed-by: Brian Osman <brianosman@google.com>
Reviewed-by: Leon Scroggins <scroggo@google.com>
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Matt Sarett <msarett@google.com>

1 files changed, 8 insertions, 4 deletions

diff --git a/src/images/SkImageEncoder.cpp b/src/images/SkImageEncoder.cpp
index f135a02063..fecadbf82a 100644
--- a/src/images/SkImageEncoder.cpp
+++ b/src/images/SkImageEncoder.cpp
@@ -16,10 +16,14 @@ bool SkEncodeImage(SkWStream* dst, const SkPixmap& src,
         return SkEncodeImageWithWIC(dst, src, format, quality);
     #else
         switch(format) {
-            case SkEncodedImageFormat::kJPEG: return SkEncodeImageAsJPEG(dst, src, quality);
-            case SkEncodedImageFormat::kPNG:  return SkEncodeImageAsPNG(dst, src);
-            case SkEncodedImageFormat::kWEBP: return SkEncodeImageAsWEBP(dst, src, quality);
-            default:                          return false;
+            case SkEncodedImageFormat::kJPEG:
+                return SkEncodeImageAsJPEG(dst, src, quality);
+            case SkEncodedImageFormat::kPNG:
+                return SkEncodeImageAsPNG(dst, src, SkEncodeOptions());
+            case SkEncodedImageFormat::kWEBP:
+                return SkEncodeImageAsWEBP(dst, src, quality);
+            default:
+                return false;
         }
     #endif
 }