Fix SkClassifyCubic for near-quadratics

Fixes the threshold logic for "0 ~= d1 && 0 ~= d2".

Previously, if d1 and d2 were both near zero, but on opposite sides
of the threshold, the curve could be misclassified as kCuspAtInfinity
and drawn incorrectly.

Bug: skia:
Change-Id: I65f30ddebf0a4a0b933610d8cc1a2f489efc99e4
Commit-Queue: Chris Dalton <>
Reviewed-by: Cary Clark <>
2 files changed