ignore max curvature at end point

When a stroked cubic folds back on itself, the
stroker draws a round join.
If the max curvature is at
the endpoint, skip the join.

R=reed@google.com
BUG=skia:6083

Change-Id: I45e429432fcec311fa1115058515639370fe9a16
Reviewed-on: https://skia-review.googlesource.com/6606
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Cary Clark <caryclark@google.com>
2 files changed