This API has existed for two and a half years now, with no
API changes over the last year, and is widely used in production,
code so it makes sense to consider it stable.

Change-Id: I10e38c37fb8c13e22124ef0985f4b0bd8d4615fd
Reviewed-on: https://chromium-review.googlesource.com/c/1461999Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59576}