Use SkJpegEncoder in gfx jpeg_codec

ui/gfx/codec/jpeg_codec.h

Index: ui/gfx/codec/jpeg_codec.h
diff --git a/ui/gfx/codec/jpeg_codec.h b/ui/gfx/codec/jpeg_codec.h
index 5d10be59cb1e3f21dcb79e3c2677630decc2d469..2e3b6c7aaedaf36c63ee14147a47f08cefbcd488 100644
--- a/ui/gfx/codec/jpeg_codec.h
+++ b/ui/gfx/codec/jpeg_codec.h
@@ -10,6 +10,7 @@
 #include <memory>
 #include <vector>
 
+#include "third_party/skia/include/core/SkImageInfo.h"
 #include "ui/gfx/codec/codec_export.h"
 
 class SkBitmap;
@@ -23,10 +24,6 @@ namespace gfx {
 class CODEC_EXPORT JPEGCodec {
  public:
   enum ColorFormat {
-    // 3 bytes per pixel (packed), in RGB order regardless of endianness.
-    // This is the native JPEG format.
-    FORMAT_RGB,
-
     // 4 bytes per pixel, in RGBA order in mem regardless of endianness.
     FORMAT_RGBA,
 
@@ -49,18 +46,22 @@ class CODEC_EXPORT JPEGCodec {
   static LibraryVariant JpegLibraryVariant();
 
   // Encodes the given raw 'input' data, with each pixel being represented as
-  // given in 'format'. The encoded JPEG data will be written into the supplied
-  // vector and true will be returned on success. On failure (false), the
-  // contents of the output buffer are undefined.
+  // given in 'colorType'. The encoded JPEG data will be written into the
+  // supplied vector and true will be returned on success. On failure (false),
+  // the contents of the output buffer are undefined.
   //
   // w, h: dimensions of the image
   // row_byte_width: the width in bytes of each row. This may be greater than
   //   w * bytes_per_pixel if there is extra padding at the end of each row
   //   (often, each row is padded to the next machine word).
   // quality: an integer in the range 0-100, where 100 is the highest quality.
-  static bool Encode(const unsigned char* input, ColorFormat format,
-                     int w, int h, int row_byte_width,
-                     int quality, std::vector<unsigned char>* output);
+  static bool Encode(const unsigned char* input,
+                     SkColorType colorType,

[dcheng, 2017/06/02 15:35:00]

Nit: color_type

From a symmetry perspective, it's a bit odd that Decode() takes a ColorFormat
while Encode() takes a SkColorType. Will we have eventual consistency here?

[scroggo_chromium, 2017/06/02 17:35:51]

Yes. We're in the process of merging Skia's decoders with Blink's, and we'd like
to use the same decoders here, too. At that point I think it makes sense to use
an SkColorType for Decode.

[msarett1, 2017/06/07 18:01:14]

Yes, I think this is a good future goal.

+                     int w,
+                     int h,
+                     int row_byte_width,
+                     int quality,
+                     std::vector<unsigned char>* output);
 
   // Decodes the JPEG data contained in input of length input_size. The
   // decoded data will be placed in *output with the dimensions in *w and *h