Add flag for future Skia CL

skia CL: https://skia-review.googlesource.com/c/21105/

NOTRY=True

Bug: 
Change-Id: I796e08bc851ab31b30d15f4b3926df22d5f85b32
Reviewed-on: https://chromium-review.googlesource.com/552677
Commit-Queue: Mike Reed <reed@chromium.org>
Reviewed-by: Florin Malita <fmalita@chromium.org>
Cr-Commit-Position: refs/heads/master@{#482997}
1 file changed