GrTessellator: add a #define for max aa verb count.

We'd like to increase the maximum verb count for the edge-AA
tessellating path renderer. In order to protect clients from this
change, we allow them to set their own value.

Bug:805031
Change-Id: I5d41059a217f059998d418d51fcc8c88464ef4da
Reviewed-on: https://skia-review.googlesource.com/98886
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Stephen White <senorblanco@chromium.org>
diff --git a/src/gpu/ops/GrTessellatingPathRenderer.cpp b/src/gpu/ops/GrTessellatingPathRenderer.cpp
index 8602d00..8eaadf0 100644
--- a/src/gpu/ops/GrTessellatingPathRenderer.cpp
+++ b/src/gpu/ops/GrTessellatingPathRenderer.cpp
@@ -24,6 +24,10 @@
 
 #include <stdio.h>
 
+#ifndef GR_AA_TESSELLATOR_MAX_VERB_COUNT
+#define GR_AA_TESSELLATOR_MAX_VERB_COUNT 10
+#endif
+
 /*
  * This path renderer tessellates the path into triangles using GrTessellator, uploads the
  * triangles to a vertex buffer, and renders them with a single draw call. It can do screenspace
@@ -147,7 +151,7 @@
     if (GrAAType::kCoverage == args.fAAType) {
         SkPath path;
         args.fShape->asPath(&path);
-        if (path.countVerbs() > 10) {
+        if (path.countVerbs() > GR_AA_TESSELLATOR_MAX_VERB_COUNT) {
             return CanDrawPath::kNo;
         }
     } else if (!args.fShape->hasUnstyledKey()) {