Rolling v8/buildtools to e27b1f1459452013ce59c9d5dbc93c88982cb76e

Rolling v8/tools/clang to 6449b18afaa80290fd8930c3a42c80908505f41f

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

Review URL: https://codereview.chromium.org/1660143007

Cr-Commit-Position: refs/heads/master@{#33714}