Many old pathops-related fuzz failures have built up while
the codebase was under a state a flux. Now that the code
is stable, address these failures.
Most of the CL plumbs the debug global state to downstream
routines so that, if the data is not trusted (ala fuzzed)
the function can safely exit without asserting.
TBR=reed@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2426173002
Review-Url: https://chromiumcodereview.appspot.com/2426173002
The cubic line intersection math empirically works 99.99% of the time (fails 3100 out of 1B random tests) but when it fails, an intersection may be missed altogether.
The binary search is may not find a solution if the cubic line failed to find any solutions at all, but so far that case hasn't arisen.
BUG=skia:2504
TBR=reed@google.com
Author: caryclark@google.com
Review URL: https://codereview.chromium.org/266063003
git-svn-id: http://skia.googlecode.com/svn/trunk@14614 2bbb7eff-a529-9590-31e7-b0007b416f81