Add isSingleComponent bool to getConstantColorComponent

src/gpu/effects/GrSingleTextureEffect.h

Index: src/gpu/effects/GrSingleTextureEffect.h
diff --git a/src/gpu/effects/GrSingleTextureEffect.h b/src/gpu/effects/GrSingleTextureEffect.h
index 6349ee7896af677ba06dcc679445719b7e42a805..caf04771c5eb29d73d322a7da76159c41df3c575 100644
--- a/src/gpu/effects/GrSingleTextureEffect.h
+++ b/src/gpu/effects/GrSingleTextureEffect.h
@@ -44,16 +44,16 @@ protected:
     }
 
     /**
-     * Can be used as a helper to implement subclass getConstantColorComponents(). It assumes that
+     * Can be used as a helper to implement subclass onComputeInvarientOutput(). It assumes that
      * the subclass output color will be a modulation of the input color with a value read from the
      * texture.
      */
-    void updateConstantColorComponentsForModulation(GrColor* color, uint32_t* validFlags) const {
-        if ((*validFlags & kA_GrColorComponentFlag) && 0xFF == GrColorUnpackA(*color) &&
-            GrPixelConfigIsOpaque(this->texture(0)->config())) {
-            *validFlags = kA_GrColorComponentFlag;
+    void updateInvarientOutputForModulation(InvarientOutput* invarientOutput) const {
+        if (invarientOutput->hasOpaqueAlpha()
+            && GrPixelConfigIsOpaque(this->texture(0)->config())) {
+            invarientOutput->validFlags = kA_GrColorComponentFlag;
         } else {
-            *validFlags = 0;
+            invarientOutput->validFlags = 0;
         }
     }