These tests stress pathops by describing the union of circle-like paths that have tiny line segments embedded and double back to create near-coincident conditions.

The fixes include
- detect when finding the active top loops between two possible answers
- preflight chasing winding to ensure answer is consistent
- binary search more often when quadratic intersection fails
- add more failure paths when an intersect is missed

While this fixes the chrome bug, reenabling path ops in svg should be deferred until additional fixes are landed.

TBR=
BUG=421132

Committed: https://skia.googlesource.com/skia/+/6f726addf3178b01949bb389ef83cf14a1d7b6b2

Review URL: https://codereview.chromium.org/633393002
diff --git a/gyp/pathops_unittest.gypi b/gyp/pathops_unittest.gypi
index 9e070ab..5117b63 100644
--- a/gyp/pathops_unittest.gypi
+++ b/gyp/pathops_unittest.gypi
@@ -33,6 +33,7 @@
     '../tests/PathOpsDTriangleTest.cpp',
     '../tests/PathOpsDVectorTest.cpp',
     '../tests/PathOpsExtendedTest.cpp',
+    '../tests/PathOpsFuzz763Test.cpp',
     '../tests/PathOpsInverseTest.cpp',
     '../tests/PathOpsLineIntersectionTest.cpp',
     '../tests/PathOpsLineParametetersTest.cpp',