Rolling v8/third_party/icu to 42c58d4e49f2250039f0e98d43e0b76e8f5ca024

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

Review URL: https://codereview.chromium.org/1420993008

Cr-Commit-Position: refs/heads/master@{#31813}