Change SkShader;asFragmentProcessor signature to no longer take skpaint\grcolor*

src/gpu/effects/GrPorterDuffXferProcessor.cpp

Index: src/gpu/effects/GrPorterDuffXferProcessor.cpp
diff --git a/src/gpu/effects/GrPorterDuffXferProcessor.cpp b/src/gpu/effects/GrPorterDuffXferProcessor.cpp
index ff857f4e0df62b72f4275c0b65526765da194ab4..022c44a5bd4a8594b3ffc4bb85eb72abaec96d1b 100644
--- a/src/gpu/effects/GrPorterDuffXferProcessor.cpp
+++ b/src/gpu/effects/GrPorterDuffXferProcessor.cpp
@@ -755,7 +755,7 @@ bool GrPorterDuffXPFactory::willReadDstColor(const GrCaps& caps,
 
 GR_DEFINE_XP_FACTORY_TEST(GrPorterDuffXPFactory);
 
-GrXPFactory* GrPorterDuffXPFactory::TestCreate(GrProcessorTestData* d) {
+const GrXPFactory* GrPorterDuffXPFactory::TestCreate(GrProcessorTestData* d) {
     SkXfermode::Mode mode = SkXfermode::Mode(d->fRandom->nextULessThan(SkXfermode::kLastCoeffMode));
     return GrPorterDuffXPFactory::Create(mode);
 }