converted GrAARectEffect to SkSL

Bug: skia:
Change-Id: I08254806fe7cb97dab21c5625aa16dd34aea9468
Reviewed-on: https://skia-review.googlesource.com/72120
Reviewed-by: Chris Dalton <csmartdalton@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
diff --git a/gn/gpu.gni b/gn/gpu.gni
index c364c29..e283a9f 100644
--- a/gn/gpu.gni
+++ b/gn/gpu.gni
@@ -314,6 +314,8 @@
   "$_src/gpu/ccpr/GrCoverageCountingPathRenderer.cpp",
   "$_src/gpu/ccpr/GrCoverageCountingPathRenderer.h",
 
+  "$_src/gpu/effects/GrAARectEffect.cpp",
+  "$_src/gpu/effects/GrAARectEffect.h",
   "$_src/gpu/effects/GrArithmeticFP.cpp",
   "$_src/gpu/effects/GrArithmeticFP.h",
   "$_src/gpu/effects/GrBlurredEdgeFragmentProcessor.cpp",