deps: backport 6e9e2e5 from upstream V8

Original commit message:

  [heap] Move SweeperTask to CancelableTask
  This mitigates the problem of blocking on the main thread when the
  platform is unable to execute background tasks in a timely manner.

  Bug: v8:6655
  Change-Id: Icdaae744ee73146b86b9a28c8035138746721971
  Reviewed-on: https://chromium-review.googlesource.com/595467


  Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
  Cr-Commit-Position: refs/heads/master@{#47036}

PR-URL: https://github.com/nodejs/node/pull/14001


Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>