fuzz wednesday

Add debug 'skip assert' access to SkCoincidentSpans.
That permits suppressing asserts to make it easier
to detect when this fuzz data generates unparsable
data.

TBR=reed@google.com
BUG=631564, 631992
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2186973002

Review-Url: https://codereview.chromium.org/2186973002
4 files changed