Use SkJpegEncoder in gfx jpeg_codec

chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_test_utils.cc

Index: chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_test_utils.cc
diff --git a/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_test_utils.cc b/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_test_utils.cc
index 87bc037538820ee3b7870f3ecc8054392448c6cd..71a591ba41285fc80792b9344daba135a2140032 100644
--- a/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_test_utils.cc
+++ b/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_test_utils.cc
@@ -87,15 +87,12 @@ bool CreateJPEGImage(int width,
   bitmap.allocN32Pixels(width, height);
   bitmap.eraseColor(color);
 
+  SkPixmap pixmap;
+  bool success = bitmap.peekPixels(&pixmap);

[dcheng, 2017/06/12 20:35:43]

Realistically, when can we expect failure? What if the bitmap is
0-width/0-height?

[msarett1, 2017/06/12 20:57:56]

This will never fail if a version of allocPixels() has already been called and
succeeds.  Note that allocN32Pixels() above will crash if it fails.

+  DCHECK(success);
+
   const int kQuality = 80;
-  if (!gfx::JPEGCodec::Encode(
-          static_cast<const unsigned char*>(bitmap.getPixels()),
-          gfx::JPEGCodec::FORMAT_SkBitmap,
-          width,
-          height,
-          bitmap.rowBytes(),
-          kQuality,
-          output)) {
+  if (!gfx::JPEGCodec::Encode(pixmap, kQuality, output)) {
     LOG(ERROR) << "Unable to encode " << width << "x" << height << " bitmap";
     return false;
   }