Add shader based blending of kPlus for configs that need clamping

This effectively reverts https://skia-review.googlesource.com/c/skia/+/140500
and relands https://skia-review.googlesource.com/c/skia/+/48183.

Bug: skia:8871
Change-Id: I6b1d5daa3d319e0c078e553926ed9166cca9a24a
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/199930
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
diff --git a/tests/ProcessorTest.cpp b/tests/ProcessorTest.cpp
index 09f24b52..2885a71 100644
--- a/tests/ProcessorTest.cpp
+++ b/tests/ProcessorTest.cpp
@@ -45,13 +45,13 @@
 
     FixedFunctionFlags fixedFunctionFlags() const override { return FixedFunctionFlags::kNone; }
 
-    GrProcessorSet::Analysis finalize(
-            const GrCaps& caps, const GrAppliedClip* clip, GrFSAAType fsaaType) override {
+    GrProcessorSet::Analysis finalize(const GrCaps& caps, const GrAppliedClip* clip,
+                                      GrFSAAType fsaaType, GrClampType clampType) override {
         static constexpr GrProcessorAnalysisColor kUnknownColor;
         SkPMColor4f overrideColor;
         return fProcessors.finalize(
                 kUnknownColor, GrProcessorAnalysisCoverage::kNone, clip,
-                &GrUserStencilSettings::kUnused, fsaaType, caps, &overrideColor);
+                &GrUserStencilSettings::kUnused, fsaaType, caps, clampType, &overrideColor);
     }
 
 private: