Add isSingleComponent bool to getConstantColorComponent

src/effects/SkPerlinNoiseShader.cpp

Index: src/effects/SkPerlinNoiseShader.cpp
diff --git a/src/effects/SkPerlinNoiseShader.cpp b/src/effects/SkPerlinNoiseShader.cpp
index 88e6caddb9d6ee6f4f2aec32a505b59c10de08bf..43197dedf208fef30b5c5d5cbcca1457cdacd809 100644
--- a/src/effects/SkPerlinNoiseShader.cpp
+++ b/src/effects/SkPerlinNoiseShader.cpp
@@ -586,6 +586,11 @@ private:
                fPaintingData->fStitchDataInit == s.fPaintingData->fStitchDataInit;
     }
 
+    void onComputeInvariantOutput(InvariantOutput* inout) const SK_OVERRIDE {
+        inout->fValidFlags = 0; // This is noise. Nothing is constant.
+        inout->fIsSingleComponent = false;
+    }
+
     GrPerlinNoiseEffect(SkPerlinNoiseShader::Type type,
                         int numOctaves, bool stitchTiles,
                         SkPerlinNoiseShader::PaintingData* paintingData,
@@ -616,10 +621,6 @@ private:
     GrTextureAccess                 fNoiseAccess;
     SkPerlinNoiseShader::PaintingData *fPaintingData;
 
-    void getConstantColorComponents(GrColor*, uint32_t* validFlags) const SK_OVERRIDE {
-        *validFlags = 0; // This is noise. Nothing is constant.
-    }
-
 private:
     typedef GrFragmentProcessor INHERITED;
 };