Add more specialized fragment builders

src/effects/SkPixelXorXfermode.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkPixelXorXfermode.h"
 #include "SkColorPriv.h"
 #include "SkReadBuffer.h"
@@ skipping 154 matching lines @@
 
     GR_DECLARE_FRAGMENT_PROCESSOR_TEST;
     typedef GrFragmentProcessor INHERITED;
 };
 
 ///////////////////////////////////////////////////////////////////////////////
 
 class GLPixelXorFP : public GrGLSLFragmentProcessor {
 public:
     void emitCode(EmitArgs& args) override {
-        GrGLSLFragmentBuilder* fragBuilder = args.fFragBuilder;
+        GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
         SkString dstColor("dstColor");
         this->emitChild(0, nullptr, &dstColor, args);
 
         fOpColorUni = args.fUniformHandler->addUniform(kFragment_GrShaderFlag,
                                                        kVec3f_GrSLType, kHigh_GrSLPrecision,
                                                        "opColor");
         const char* kOpColorUni = args.fUniformHandler->getUniformCStr(fOpColorUni);
 
         add_pixelxor_code(fragBuilder, args.fInputColor, dstColor.c_str(),
                           args.fOutputColor, kOpColorUni);
@@ skipping 185 matching lines @@
 const GrFragmentProcessor* SkPixelXorXfermode::getFragmentProcessorForImageFilter(
                                                         const GrFragmentProcessor* dst) const {
     return PixelXorFP::Create(fOpColor, dst);
 }
 
 GrXPFactory* SkPixelXorXfermode::asXPFactory() const {
     return GrPixelXorXPFactory::Create(fOpColor);
 }
 
 #endif