added support for PLS path rendering

include/gpu/effects/GrCoverageSetOpXP.h

Index: include/gpu/effects/GrCoverageSetOpXP.h
diff --git a/include/gpu/effects/GrCoverageSetOpXP.h b/include/gpu/effects/GrCoverageSetOpXP.h
index 097a890d569c1f72cd80cbfe550da903d04ecb57..561ddf5da355c5414d63f5e72d63ed91c2a7b153 100644
--- a/include/gpu/effects/GrCoverageSetOpXP.h
+++ b/include/gpu/effects/GrCoverageSetOpXP.h
@@ -34,12 +34,6 @@ private:
                                            bool hasMixedSamples,
                                            const DstTexture*) const override;
 
-    bool willReadDstColor(const GrCaps& /*caps*/,
-                          const GrPipelineOptimizations& /*optimizations*/,
-                          bool /*hasMixedSamples*/) const override {
-        return false;
-    }
-
     bool onIsEqual(const GrXPFactory& xpfBase) const override {
         const GrCoverageSetOpXPFactory& xpf = xpfBase.cast<GrCoverageSetOpXPFactory>();
         return fRegionOp == xpf.fRegionOp;