Add SkColorSpacePrimaries to help with making D50 matrices

src/core/SkColorSpace.cpp

Index: src/core/SkColorSpace.cpp
diff --git a/src/core/SkColorSpace.cpp b/src/core/SkColorSpace.cpp
index abdd647a258c173e329a4db1f87b550192e14acb..3b892da11e8f724fff618ef04e3f9dcc71449c8b 100644
--- a/src/core/SkColorSpace.cpp
+++ b/src/core/SkColorSpace.cpp
@@ -125,6 +125,47 @@ sk_sp<SkColorSpace> SkColorSpace::NewRGB(GammaNamed gammaNamed, const SkMatrix44
     return SkColorSpace_Base::NewRGB(gammaNamed, toXYZD50);
 }
 
+sk_sp<SkColorSpace> SkColorSpace::NewRGB(const GammaCoefficients& coeffs,
+                                         const SkMatrix44& toXYZD50) {
+    // TODO: Check if coeffs match sRGB, 2.2, or linear.
+    // TODO: Make sure coefficients are non-crazy.  Return nullptr if they are.
+    void* memory = sk_malloc_throw(sizeof(SkGammas) + sizeof(SkColorSpace::GammaParams));
+    sk_sp<SkGammas> gammas = sk_sp<SkGammas>(new (memory) SkGammas());
+    void* storage = SkTAddOffset<void>(memory, sizeof(SkGammas));
+     memcpy(storage, &coeffs, sizeof(SkColorSpace::GammaParams));
+     gammas->fRedType = SkGammas::Type::kParam_Type;
+     gammas->fGreenType = SkGammas::Type::kParam_Type;
+     gammas->fBlueType = SkGammas::Type::kParam_Type;
+
+     SkGammas::Data data;
+     data.fParamOffset = 0;
+     gammas->fRedData = data;
+     gammas->fGreenData = data;
+     gammas->fBlueData = data;
+     return sk_sp<SkColorSpace>(new SkColorSpace_Base(nullptr, kNonStandard_GammaNamed,
+                                                      std::move(gammas), toXYZD50, nullptr);
+}
+
+sk_sp<SkColorSpace> SkColorSpace::NewRGB(GammaNamed gammaNamed, const Primaries& primaries) {
+    SkMatrix44 toXYZD50;
+    // TODO: Implement primaries_to_toXYZD50.
+    if (!primaries_to_toXYZD50(&toXYZD50, primaries)) {
+        return nullptr;
+    }
+
+    return NewRGB(gammaNamed, toXYZD50)
+}
+
+sk_sp<SkColorSpace> SkColorSpace::NewRGB(const GammaCoefficients& coeffs,
+                                         const Primaries& primaries) {
+    SkMatrix44 toXYZD50;
+    if (!primaries_to_toXYZD50(&toXYZD50, primaries)) {
+        return nullptr;
+    }
+
+    return NewRGB(coeffs, toXYZD50)
+}
+
 sk_sp<SkColorSpace> SkColorSpace::NewNamed(Named named) {
     static SkOnce sRGBOnce;
     static sk_sp<SkColorSpace> sRGB;
@@ -251,6 +292,15 @@ size_t SkColorSpace::writeToMemory(void* memory) const {
                 return sizeof(ColorSpaceHeader) + 12 * sizeof(float);
             }
             default:
+                // TODO: This case gets trickier.  The code below exists because I allow
+                //       SkPngCodec to call a constructor with float gammas.
+                //       I think the best thing to do would be:
+                //       (1) Fix SkPngCodec to call one of the new constructors.
+                //       (2) Handle serializing the parametric gammas here.
+                // TODO: In a separate CL, remove the idea of "exponential" gammas.
+                //       These can be consumed by the parametric case.  Maybe this CL
+                //       should land first.
+
                 // Otherwise, write the gamma values and the matrix.
                 if (memory) {
                     *((ColorSpaceHeader*) memory) =
@@ -354,6 +404,8 @@ sk_sp<SkColorSpace> SkColorSpace::Deserialize(const void* data, size_t length) {
             return NewICC(data, profileSize);
         }
         case ColorSpaceHeader::kFloatGamma_Flag: {
+            // TODO: This needs to be fixed to match the new version of serialize().
+
             if (length < 15 * sizeof(float)) {
                 return nullptr;
             }
@@ -415,6 +467,7 @@ bool SkColorSpace::Equals(const SkColorSpace* src, const SkColorSpace* dst) {
             if (src->fGammaNamed != dst->fGammaNamed) {
                 return false;
             }
+            // This should still work :).
 
             // It is unlikely that we will reach this case.
             sk_sp<SkData> srcData = src->serialize();