fix valgrind

(A recently added fuzzer test broke the valgrind bot, intentionally,
to isolate an uninitialized memory bug.)

If the conic has ordered points, but cannot be broken into parts,
treat it as if it were monotonic.

R=reed@google.com
BUG=skia:4757
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1568513002

Review URL: https://codereview.chromium.org/1568513002
1 file changed