Introduce GrColorSpaceXform, for gamut conversion on textures

src/gpu/effects/GrYUVEffect.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrYUVEffect.h"
 
 #include "GrCoordTransform.h"
@@ skipping 134 matching lines @@
         GrGLSLProgramDataManager::UniformHandle fMatrixUni;
 
         typedef GrGLSLFragmentProcessor INHERITED;
     };
 
 private:
     YUVtoRGBEffect(GrTexture* yTexture, GrTexture* uTexture, GrTexture* vTexture,
                    const SkMatrix yuvMatrix[3], GrTextureParams::FilterMode uvFilterMode,
                    SkYUVColorSpace colorSpace, bool nv12)
         : fYTransform(kLocal_GrCoordSet, yuvMatrix[0], yTexture, GrTextureParams::kNone_FilterMode)
-        , fYAccess(yTexture)
+        , fYAccess(yTexture, nullptr)
         , fUTransform(kLocal_GrCoordSet, yuvMatrix[1], uTexture, uvFilterMode)
-        , fUAccess(uTexture, uvFilterMode)
-        , fVAccess(vTexture, uvFilterMode)
+        , fUAccess(uTexture, nullptr, uvFilterMode)
+        , fVAccess(vTexture, nullptr, uvFilterMode)
         , fColorSpace(colorSpace)
         , fNV12(nv12) {
         this->initClassID<YUVtoRGBEffect>();
         this->addCoordTransform(&fYTransform);
         this->addTextureAccess(&fYAccess);
         this->addCoordTransform(&fUTransform);
         this->addTextureAccess(&fUAccess);
         if (!fNV12) {
             fVTransform = GrCoordTransform(kLocal_GrCoordSet, yuvMatrix[2], vTexture, uvFilterMode);
             this->addCoordTransform(&fVTransform);
@@ skipping 226 matching lines @@
     return sk_sp<GrFragmentProcessor>(
         new RGBToYUVEffect(std::move(rgbFP), colorSpace, RGBToYUVEffect::kU_OutputChannels));
 }
 
 sk_sp<GrFragmentProcessor>
 GrYUVEffect::MakeRGBToV(sk_sp<GrFragmentProcessor> rgbFP, SkYUVColorSpace colorSpace) {
     SkASSERT(rgbFP);
     return sk_sp<GrFragmentProcessor>(
         new RGBToYUVEffect(std::move(rgbFP), colorSpace, RGBToYUVEffect::kV_OutputChannels));
 }