More flexible rect->quad variants

- take spans
- allow Direction (cw/ccw) to be specified

(inspired by SkPathData work)

Change-Id: I459a130d3c3ed841817357e758d2a2a49b793dab
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/1035517
Reviewed-by: Eric Boren <borenet@google.com>
Reviewed-by: Daniel Dilan <danieldilan@google.com>
Commit-Queue: Mike Reed <mike@reedtribe.org>
Reviewed-by: Florin Malita <fmalita@google.com>
5 files changed