Pin miter sin half angle to 0 in GrAAConvexTessellator.

Covers slightly concave ring outsets.

Bug: chromium:883331
Change-Id: I1d3d5be5d2ad9d7cd8953356164e9763922b274a
Reviewed-on: https://skia-review.googlesource.com/154541
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
1 file changed