Correct sRGB <-> linear everywhere.

src/core/SkColor.cpp

Index: src/core/SkColor.cpp
diff --git a/src/core/SkColor.cpp b/src/core/SkColor.cpp
index a1404a27e360288ad930d45cc3c0a1c876593f85..39e9aafa929f0d30a971a40bb10781d8a0d3bf36 100644
--- a/src/core/SkColor.cpp
+++ b/src/core/SkColor.cpp
@@ -106,10 +106,7 @@ SkColor SkHSVToColor(U8CPU a, const SkScalar hsv[3]) {
 #include "SkHalf.h"
 
 SkPM4f SkPM4f::FromPMColor(SkPMColor c) {
-    Sk4f value = to_4f_rgba(c);
-    SkPM4f c4;
-    (value * Sk4f(1.0f / 255)).store(&c4);
-    return c4;
+    return From4f(swizzle_rb_if_bgra(Sk4f_fromL32(c)));
 }
 
 SkColor4f SkPM4f::unpremul() const {
@@ -152,21 +149,14 @@ void SkPM4f::assertIsUnit() const {
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
-SkColor4f SkColor4f::FromColor(SkColor c) {
-    Sk4f value = SkNx_shuffle<2,1,0,3>(SkNx_cast<float>(Sk4b::Load(&c)));
-    SkColor4f c4;
-    (value * Sk4f(1.0f / 255)).store(&c4);
-    c4.fR = srgb_to_linear(c4.fR);
-    c4.fG = srgb_to_linear(c4.fG);
-    c4.fB = srgb_to_linear(c4.fB);
-    return c4;
+SkColor4f SkColor4f::FromColor(SkColor bgra) {
+    SkColor4f rgba;
+    swizzle_rb(Sk4f_fromS32(bgra)).store(rgba.vec());
+    return rgba;
 }
 
 SkColor SkColor4f::toSkColor() const {
-    SkColor result;
-    Sk4f value = Sk4f(linear_to_srgb(fB), linear_to_srgb(fG), linear_to_srgb(fR), fA);
-    SkNx_cast<uint8_t>(value * Sk4f(255) + Sk4f(0.5f)).store(&result);
-    return result;
+    return Sk4f_toS32(swizzle_rb(Sk4f::Load(this->vec())));
 }
 
 SkColor4f SkColor4f::Pin(float r, float g, float b, float a) {