Revert "rebaseline SK_LEGACY_OP_COLOR_AS_BYTES"

This reverts commit ea1a3ea1.

Reason for revert: broke fast/canvas/canvas-composite-shadow.html on Win10.
https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/WebKit%20Win10/43023

Original change's description:
> rebaseline SK_LEGACY_OP_COLOR_AS_BYTES
> 
> This flag was repurposed... the real thing we're rebaselining
> is https://skia-review.googlesource.com/c/skia/+/167264, which
> affects situations with solid colors and unusual blend modes.
> 
> Change-Id: I1da6486ca54d5f6c60bb0b04db05f6dc92487039
> Reviewed-on: https://chromium-review.googlesource.com/c/1316754
> Commit-Queue: Florin Malita <fmalita@chromium.org>
> Reviewed-by: Florin Malita <fmalita@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#605216}

TBR=fmalita@chromium.org,mtklein@chromium.org

Change-Id: I1592f49dd54abd4da3f9abbd3d85cce40cddc5d4
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/1317071Reviewed-by: Kunihiko Sakamoto <ksakamoto@chromium.org>
Commit-Queue: Kunihiko Sakamoto <ksakamoto@chromium.org>
Cr-Commit-Position: refs/heads/master@{#605242}

skia/config/SkUserConfig.h

@@ -139,6 +139,8 @@ SK_API void SkDebugf_FileLine(const char* file, int line, bool fatal,
 #   define SK_SUPPORT_LEGACY_ANISOTROPIC_MIPMAP_SCALE
 #endif
 
+#define SK_LEGACY_OP_COLOR_AS_BYTES
+
 // Remove this after we fixed all the issues related to the new SDF algorithm
 // (https://codereview.chromium.org/1643143002)
 #ifndef SK_USE_LEGACY_DISTANCE_FIELDS