Myers: Point and Segment

Definition of Point and Segment for the Myers algorithm.

The paper is here:
https://drive.google.com/file/d/1lYw5m8ryC5C1DiG1NIHOV5tp4U4GdgH2/view?usp=drive_link

To see how this change fits in to future CLs consult:
https://skia-review.googlesource.com/c/skia/+/784551

Bug: b/297220808
Change-Id: I1d043cc7ee31adabdac6acca485a77e5e7207122
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/789158
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Herb Derby <herb@google.com>
7 files changed