GrTessellator: remove collinear vertices.

During sanitize_contours(), remove any points which are collinear
with their previous and next points.

Bug: skia:8503
Change-Id: Iba1df73b15a92047302bc26f01cb79f4de118760
Reviewed-on: https://skia-review.googlesource.com/130206
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Stephen White <senorblanco@chromium.org>
1 file changed