Add in shader blending for CoverageSetOp XP

src/gpu/glsl/GrGLSLXferProcessor.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 "glsl/GrGLSLXferProcessor.h"
 
 #include "GrXferProcessor.h"
@@ skipping 45 matching lines @@
         }
 
         fragBuilder->codeAppendf("vec4 %s = ", dstColor);
         fragBuilder->appendTextureLookup(args.fSamplers[0], "_dstTexCoord", kVec2f_GrSLType);
         fragBuilder->codeAppend(";");
     }
 
     this->emitBlendCodeForDstRead(args.fPB,
                                   fragBuilder,
                                   args.fInputColor,
+                                  args.fInputCoverage,
                                   dstColor,
                                   args.fOutputPrimary,
+                                  args.fOutputSecondary,
                                   args.fXP);
-
-    // Apply coverage.
-    if (args.fXP.dstReadUsesMixedSamples()) {
-        if (args.fInputCoverage) {
-            fragBuilder->codeAppendf("%s *= %s;", args.fOutputPrimary, args.fInputCoverage);
-            fragBuilder->codeAppendf("%s = %s;", args.fOutputSecondary, args.fInputCoverage);
-        } else {
-            fragBuilder->codeAppendf("%s = vec4(1.0);", args.fOutputSecondary);
-        }
-    } else if (args.fInputCoverage) {
-        fragBuilder->codeAppendf("%s = %s * %s + (vec4(1.0) - %s) * %s;",
-                                 args.fOutputPrimary, args.fInputCoverage,
-                                 args.fOutputPrimary, args.fInputCoverage, dstColor);
-    }
 }
 
 void GrGLSLXferProcessor::setData(const GrGLSLProgramDataManager& pdm, const GrXferProcessor& xp) {
     if (xp.getDstTexture()) {
         if (fDstTopLeftUni.isValid()) {
             pdm.set2f(fDstTopLeftUni, static_cast<float>(xp.dstTextureOffset().fX),
                       static_cast<float>(xp.dstTextureOffset().fY));
             pdm.set2f(fDstScaleUni, 1.f / xp.getDstTexture()->width(),
                       1.f / xp.getDstTexture()->height());
         } else {
             SkASSERT(!fDstScaleUni.isValid());
         }
     } else {
         SkASSERT(!fDstTopLeftUni.isValid());
         SkASSERT(!fDstScaleUni.isValid());
     }
     this->onSetData(pdm, xp);
 }