Replace ModulateRGBA effect with Xfermode using modulate blend.

This reduces our code size by reusing existing components to perform
the same blend, and generates a shader that should be conceptually
equivalent (although it gives the inliner a bit more work to do).

Change-Id: Ie2203f7613503476fa9d045aba58d9ef39f3ea26
Bug: skia:10457
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/302264
Commit-Queue: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
diff --git a/src/gpu/SkGr.cpp b/src/gpu/SkGr.cpp
index 8df9db0..1dd5902 100644
--- a/src/gpu/SkGr.cpp
+++ b/src/gpu/SkGr.cpp
@@ -45,7 +45,6 @@
 #include "src/gpu/effects/generated/GrClampFragmentProcessor.h"
 #include "src/gpu/effects/generated/GrConstColorProcessor.h"
 #include "src/gpu/effects/generated/GrDitherEffect.h"
-#include "src/gpu/effects/generated/GrModulateRGBAEffect.h"
 #include "src/image/SkImage_Base.h"
 #include "src/shaders/SkShaderBase.h"
 
@@ -263,7 +262,7 @@
             if (1.0f != paintAlpha) {
                 // No gamut conversion - paintAlpha is a (linear) alpha value, splatted to all
                 // color channels. It's value should be treated as the same in ANY color space.
-                paintFP = GrModulateRGBAEffect::Make(
+                paintFP = GrFragmentProcessor::ModulateRGBA(
                         std::move(paintFP), {paintAlpha, paintAlpha, paintAlpha, paintAlpha});
             }
         } else {
@@ -286,7 +285,7 @@
             if (1.0f != paintAlpha) {
                 // No gamut conversion - paintAlpha is a (linear) alpha value, splatted to all
                 // color channels. It's value should be treated as the same in ANY color space.
-                paintFP = GrModulateRGBAEffect::Make(
+                paintFP = GrFragmentProcessor::ModulateRGBA(
                         std::move(paintFP), {paintAlpha, paintAlpha, paintAlpha, paintAlpha});
             }
         } else {