Stroking in Skia follows the SVG rules of adding end caps to degenerate
contours. Skip all degenerate contours and degenerate curves on contours
to avoid this.
Bug: skia:9820
Change-Id: I320beeeb3728f39c764729454dcb128a05524d35
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/268166
Commit-Queue: Ben Wagner <bungeman@google.com>
Reviewed-by: Herb Derby <herb@google.com>
