pathops: Cosmetic only change, update comments around ComplexBreak().

Rename loopT to splitT and make it clearer that it is not just
self intersecting loop cubics that are split.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1921173003

Review URL: https://codereview.chromium.org/1921173003
1 file changed