Revert of Add isSingleComponent bool to getConstantColorComponent

src/effects/gradients/SkGradientShader.cpp

Index: src/effects/gradients/SkGradientShader.cpp
diff --git a/src/effects/gradients/SkGradientShader.cpp b/src/effects/gradients/SkGradientShader.cpp
index 89b323a701d2c3cdc09a20114b1457e3375a3736..d25873b438502c84bd3a880f84524ed6bff21df0 100644
--- a/src/effects/gradients/SkGradientShader.cpp
+++ b/src/effects/gradients/SkGradientShader.cpp
@@ -1217,13 +1217,12 @@
     return false;
 }
 
-void GrGradientEffect::onComputeInvariantOutput(InvariantOutput* inout) const {
-    if (fIsOpaque && inout->isOpaque()) {
-        inout->fValidFlags = kA_GrColorComponentFlag;
-    } else {
-        inout->fValidFlags = 0;
-    }
-    inout->fIsSingleComponent = false;
+void GrGradientEffect::getConstantColorComponents(GrColor* color, uint32_t* validFlags) const {
+    if (fIsOpaque && (kA_GrColorComponentFlag & *validFlags) && 0xff == GrColorUnpackA(*color)) {
+        *validFlags = kA_GrColorComponentFlag;
+    } else {
+        *validFlags = 0;
+    }
 }
 
 int GrGradientEffect::RandomGradientParams(SkRandom* random,