center frame to make hairline more repo on gpus

Bug: skia:
Change-Id: Ia634f738b76e3f60b17798719f1b72db5cf213ad
Reviewed-on: https://skia-review.googlesource.com/102864
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
1 file changed