In GrAAConvexPathRenderer check whether middle quadtric control point is
close to line segment between first and last control points and if so
draw as a line.

Previously we just checked whether the middle control point was close to
either the first or last.

Bug: skia:8928
Bug: chromium:945449
Change-Id: I1f7353623c29dcdc329812c44815b80898f83625
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/204981
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
2 files changed