Use dst copies in porter duffer XP to correctly render certain blends.

src/gpu/effects/GrDisableColorXP.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 "effects/GrDisableColorXP.h"
 #include "GrProcessor.h"
 #include "gl/GrGLXferProcessor.h"
@@ skipping 82 matching lines @@
     blendInfo->fWriteColor = false;
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 GrDisableColorXPFactory::GrDisableColorXPFactory() {
     this->initClassID<GrDisableColorXPFactory>();
 }
 
 GrXferProcessor*
-GrDisableColorXPFactory::onCreateXferProcessor(const GrProcOptInfo& colorPOI,
+GrDisableColorXPFactory::onCreateXferProcessor(const GrDrawTargetCaps& caps,
+                                               const GrProcOptInfo& colorPOI,
                                                const GrProcOptInfo& covPOI,
                                                const GrDeviceCoordTexture* dstCopy) const {
     return DisableColorXP::Create();
 }
 
 GR_DEFINE_XP_FACTORY_TEST(GrDisableColorXPFactory);
 
 GrXPFactory* GrDisableColorXPFactory::TestCreate(SkRandom* random,
                                                   GrContext*,
                                                   const GrDrawTargetCaps&,
                                                   GrTexture*[]) {
     return GrDisableColorXPFactory::Create();
 }