Rolling v8/tools/clang: https://chromium.googlesource.com/chromium/src/tools/clang/+log/a9a3094..5d201de

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

Change-Id: I27cd525fb18d47ff9fcf1c60c45d251d4f36ef80
Reviewed-on: https://chromium-review.googlesource.com/484100Reviewed-by: v8 autoroll <v8-autoroll@chromium.org>
Commit-Queue: v8 autoroll <v8-autoroll@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44764}