Remove hasMixedSamples() from GrPipelineBuilder

src/gpu/effects/GrDisableColorXP.h

Index: src/gpu/effects/GrDisableColorXP.h
diff --git a/src/gpu/effects/GrDisableColorXP.h b/src/gpu/effects/GrDisableColorXP.h
index 3182eef64de78862b433bcc367214a26961e6aa6..558495451df77c8551649449dc2d823fea80a518 100644
--- a/src/gpu/effects/GrDisableColorXP.h
+++ b/src/gpu/effects/GrDisableColorXP.h
@@ -31,9 +31,7 @@ private:
                                            bool hasMixedSamples,
                                            const DstTexture* dstTexture) const override;
 
-    bool onWillReadDstColor(const GrCaps& caps,
-                            const GrPipelineOptimizations& optimizations,
-                            bool hasMixedSamples) const override {
+    bool onWillReadDstColor(const GrCaps&, const GrPipelineOptimizations&) const override {
         return false;
     }