Make XPFragmentBuilder only Builder with access to DstCopy.

src/gpu/effects/GrYUVtoRGBEffect.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 "GrYUVtoRGBEffect.h"
 
 #include "GrCoordTransform.h"
@@ skipping 48 matching lines @@
         static void GenKey(const GrProcessor&, const GrGLSLCaps&, GrProcessorKeyBuilder*) {}
 
         GLProcessor(const GrProcessor&) {}
 
         virtual void emitCode(GrGLFPBuilder* builder,
                               const GrFragmentProcessor&,
                               const char* outputColor,
                               const char* inputColor,
                               const TransformedCoordsArray& coords,
                               const TextureSamplerArray& samplers) override {
-            GrGLFPFragmentBuilder* fsBuilder = builder->getFragmentShaderBuilder();
+            GrGLFragmentBuilder* fsBuilder = builder->getFragmentShaderBuilder();
 
             const char* yuvMatrix   = NULL;
             fMatrixUni = builder->addUniform(GrGLProgramBuilder::kFragment_Visibility,
                                              kMat44f_GrSLType, kDefault_GrSLPrecision,
                                              "YUVMatrix", &yuvMatrix);
             fsBuilder->codeAppendf("\t%s = vec4(\n\t\t", outputColor);
             fsBuilder->appendTextureLookup(samplers[0], coords[0].c_str(), coords[0].getType());
             fsBuilder->codeAppend(".r,\n\t\t");
             fsBuilder->appendTextureLookup(samplers[1], coords[1].c_str(), coords[1].getType());
             fsBuilder->codeAppend(".r,\n\t\t");
@@ skipping 84 matching lines @@
 }
 
 //////////////////////////////////////////////////////////////////////////////
 
 GrFragmentProcessor*
 GrYUVtoRGBEffect::Create(GrTexture* yTexture, GrTexture* uTexture, GrTexture* vTexture,
                          SkISize sizes[3], SkYUVColorSpace colorSpace) {
     SkASSERT(yTexture && uTexture && vTexture && sizes);
     return YUVtoRGBEffect::Create(yTexture, uTexture, vTexture, sizes, colorSpace);
 }