Rolling v8/build to d4fdf55ba8b19ee50d864162c343fd1939d00fe7

Rolling v8/buildtools to 06e80a0e17319868d4a9b13f9bb6a248dc8d8b20

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

Review-Url: https://codereview.chromium.org/1977243002
Cr-Commit-Position: refs/heads/master@{#36258}