Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/b376554..ce6d3d8

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

Change-Id: Idda412143f1ff00ca10e8822acb5a0754372ee29
Reviewed-on: https://chromium-review.googlesource.com/694681Reviewed-by: v8 autoroll <v8-autoroll@chromium.org>
Commit-Queue: v8 autoroll <v8-autoroll@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48251}