SkPDF: better tolerance path conversion to quadratics

BUG=chromium:691386
Change-Id: I2cb9be7dd606b2ba61ff609f9fd81a55655901f6
Reviewed-on: https://skia-review.googlesource.com/8381
Commit-Queue: Hal Canary <halcanary@google.com>
Reviewed-by: Ben Wagner <bungeman@google.com>
Reviewed-by: Cary Clark <caryclark@google.com>
diff --git a/gn/gm.gni b/gn/gm.gni
index be3a482..fc3fc03 100644
--- a/gn/gm.gni
+++ b/gn/gm.gni
@@ -84,6 +84,7 @@
   "$_gm/convexpolyclip.cpp",
   "$_gm/convexpolyeffect.cpp",
   "$_gm/copyTo4444.cpp",
+  "$_gm/crbug_691386.cpp",
   "$_gm/croppedrects.cpp",
   "$_gm/cubicpaths.cpp",
   "$_gm/dashcircle.cpp",