Rewrite the path tessellation sample

Use the GrPathTessellators directly instead of going through
GrPathStencilFillOp. Add keyboard shortcuts to toggle between the
different path tessellators.

Bug: skia:10419
Change-Id: I5d80731d26c9a77fb0eca07a7023c50848e29f7c
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/409556
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Tyler Denniston <tdenniston@google.com>
diff --git a/src/gpu/GrProcessor.h b/src/gpu/GrProcessor.h
index ddf69ea..5e1f1f3 100644
--- a/src/gpu/GrProcessor.h
+++ b/src/gpu/GrProcessor.h
@@ -130,11 +130,11 @@
         kStencilResolveProcessor_ClassID,
         kFwidthSquircleTestProcessor_ClassID,
         kSwizzleFragmentProcessor_ClassID,
-        kTessellate_GrCubicTessellateShader_ClassID,
+        kTessellate_GrCurveMiddleOutShader_ClassID,
+        kTessellate_GrCurveTessellateShader_ClassID,
         kTessellate_GrFillBoundingBoxShader_ClassID,
         kTessellate_GrFillCubicHullShader_ClassID,
         kTessellate_GrFillTriangleShader_ClassID,
-        kTessellate_GrMiddleOutCubicShader_ClassID,
         kTessellate_GrStencilTriangleShader_ClassID,
         kTessellate_GrStrokeShader_ClassID,
         kTessellate_GrWedgeTessellateShader_ClassID,