draw: inline the generated YCbCrToRGB calls.

benchmark                      old ns/op     new ns/op     delta
BenchmarkScaleLargeDownNN      1302036       1168046       -10.29%
BenchmarkScaleLargeDownAB      3995006       3447621       -13.70%
BenchmarkScaleLargeDownBL      455470707     387598726     -14.90%
BenchmarkScaleLargeDownCR      818317661     679199442     -17.00%
BenchmarkScaleSrcYCbCr         3965076       3422325       -13.69%
BenchmarkTformABSrcYCbCr       2921253       2551934       -12.64%
BenchmarkTformCRSrcYCbCr       14839184      12263956      -17.35%

Change-Id: I60dcb5c00a30709fdc6616cbc8c2fc48ec3a8b14
Reviewed-on: https://go-review.googlesource.com/7921
Reviewed-by: Rob Pike <r@golang.org>
2 files changed