Since we have this d8 directory now, we can also use it.

R=machenbach@chromium.org

Bug: v8:7109
Change-Id: I595ceb30e1c9350ad00d5cfaf998e40294602103
Reviewed-on: https://chromium-review.googlesource.com/803214Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49817}