Use threshold of 1 texture coord value per pixel w/ nearest neighbor.

src/gpu/effects/GrYUVtoRGBEffect.cpp

Index: src/gpu/effects/GrYUVtoRGBEffect.cpp
diff --git a/src/gpu/effects/GrYUVtoRGBEffect.cpp b/src/gpu/effects/GrYUVtoRGBEffect.cpp
index 68917396f48decb551745228f39b63501cf841d0..50d0e52d6e8a20719269526e19397f9e9387b1d4 100644
--- a/src/gpu/effects/GrYUVtoRGBEffect.cpp
+++ b/src/gpu/effects/GrYUVtoRGBEffect.cpp
@@ -90,8 +90,9 @@ public:
 private:
     YUVtoRGBEffect(GrTexture* yTexture, GrTexture* uTexture, GrTexture* vTexture,
                    SkYUVColorSpace colorSpace)
-     : fCoordTransform(kLocal_GrCoordSet, GrCoordTransform::MakeDivByTextureWHMatrix(yTexture),
-                       yTexture)
+     : fCoordTransform(kLocal_GrCoordSet,
+                       GrCoordTransform::MakeDivByTextureWHMatrix(yTexture),
+                       yTexture, GrTextureParams::kNone_FilterMode)
     , fYAccess(yTexture)
     , fUAccess(uTexture)
     , fVAccess(vTexture)