Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/4161431..9d6666d

TBR=machenbach@chromium.org,vogelheim@chromium.org,hablich@chromium.org

Change-Id: I3bddd9d99ea1840cce06dcb2c5b2bed33d2e7a7b
Reviewed-on: https://chromium-review.googlesource.com/527576Reviewed-by: v8 autoroll <v8-autoroll@chromium.org>
Commit-Queue: v8 autoroll <v8-autoroll@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45788}