Add a dedicated Op for analytic round rects

Adds a GrAAFillRRectOp class that can draw any round rect, including
complex. The Op makes use of instanced rendering and fwidth().

Bug: chromium:860021
Change-Id: I3d8818a003899b56c33d35babe22cd15d3f8e110
Reviewed-on: https://skia-review.googlesource.com/c/170729
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
diff --git a/gn/gpu.gni b/gn/gpu.gni
index c880d8a..4bd632a 100644
--- a/gn/gpu.gni
+++ b/gn/gpu.gni
@@ -232,6 +232,8 @@
   "$_src/gpu/ops/GrAAConvexPathRenderer.cpp",
   "$_src/gpu/ops/GrAAConvexPathRenderer.h",
   "$_src/gpu/ops/GrAAFillRectOp.cpp",
+  "$_src/gpu/ops/GrAAFillRRectOp.cpp",
+  "$_src/gpu/ops/GrAAFillRRectOp.h",
   "$_src/gpu/ops/GrAAHairLinePathRenderer.cpp",
   "$_src/gpu/ops/GrAAHairLinePathRenderer.h",
   "$_src/gpu/ops/GrAALinearizingConvexPathRenderer.cpp",