Also extend the API to reflect this new feature.


R=jgruber@chromium.org, szuend@google.com, ulan@chromium.org

Bug: v8:8125
Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng
Change-Id: Ic7a7604a8c663ba04b324eb8902ff325a25654e7
Reviewed-on: https://chromium-review.googlesource.com/1202087Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55604}