SkVertices: Fix calculation of size needed for attr marker names

Bug: oss-fuzz:24246
Change-Id: Ib99a359b2f0c6ee55180734d6ae933b90e4f6ca8
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/303920
Commit-Queue: Brian Osman <brianosman@google.com>
Auto-Submit: Brian Osman <brianosman@google.com>
Reviewed-by: Kevin Lubick <kjlubick@google.com>
1 file changed