Refactor without turning on sse2/sse41.

This is another slice of https://skia-review.googlesource.com/c/8230/.

CQ_INCLUDE_TRYBOTS=skia.primary:Test-Win2k8-MSVC-GCE-CPU-AVX2-x86_64-Debug,Test-Win10-MSVC-Golo-GPU-GT610-x86_64-Release

Change-Id: I9a95b319c9695874c975d17d230f1569a8996f83
Reviewed-on: https://skia-review.googlesource.com/8350
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Mike Klein <mtklein@chromium.org>
3 files changed