GitLab

Update asyncGC function to the latest version to guarantee that GCs are
indeed run without stack.

Bug: chromium:843903
Change-Id: Iaa61f27cacd99854665358720d2354522b756302
Reviewed-on: https://chromium-review.googlesource.com/1238623Reviewed-by: Kentaro Hara <haraken@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#593550}