fix path op conic bugs

src/pathops/SkOpContour.cpp

Index: src/pathops/SkOpContour.cpp
diff --git a/src/pathops/SkOpContour.cpp b/src/pathops/SkOpContour.cpp
index 2e4b2ca56abfaa9540ad7c6f00e2c6b73000fbf5..df65437c97d1799fb212961758e149ae763faf45 100644
--- a/src/pathops/SkOpContour.cpp
+++ b/src/pathops/SkOpContour.cpp
@@ -42,7 +42,7 @@ void SkOpContour::toPath(SkPathWriter* path) const {
     path->deferredMove(pt);
     const SkOpSegment* segment = &fHead;
     do {
-        segment->addCurveTo(segment->head(), segment->tail(), path, true);
+        SkAssertResult(segment->addCurveTo(segment->head(), segment->tail(), path));
     } while ((segment = segment->next()));
     path->close();
 }
@@ -52,7 +52,7 @@ void SkOpContour::toReversePath(SkPathWriter* path) const {
     path->deferredMove(pt);
     const SkOpSegment* segment = fTail;
     do {
-        segment->addCurveTo(segment->tail(), segment->head(), path, true);
+        SkAssertResult(segment->addCurveTo(segment->tail(), segment->head(), path));
     } while ((segment = segment->prev()));
     path->close();
 }