add comment
TBR=reed@google.com
NOTRY=true
BUG=skia:4757
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1566733002
Review URL: https://codereview.chromium.org/1566733002
diff --git a/src/core/SkPath.cpp b/src/core/SkPath.cpp
index 757cae0..ab8d735 100644
--- a/src/core/SkPath.cpp
+++ b/src/core/SkPath.cpp
@@ -2765,6 +2765,8 @@
int* onCurveCount) {
SkConic conic(pts, weight);
SkConic chopped[2];
+ // If the data points are very large, the conic may not be monotonic but may also
+ // fail to chop. Then, the chopper does not split the original conic in two.
bool isMono = is_mono_quad(pts[0].fY, pts[1].fY, pts[2].fY) || !conic.chopAtYExtrema(chopped);
int w = winding_mono_conic(isMono ? conic : chopped[0], x, y, onCurveCount);
if (!isMono) {