Rolling v8/third_party/icu to 89dcdec16381883782b9cc9cff38e00f047a0f46

Rolling v8/tools/clang to 5b12e334ec0e571a8e1f68d028dc5427b58c17ec

TBR=machenbach@chromium.org

Review URL: https://codereview.chromium.org/1294523005

Cr-Commit-Position: refs/heads/master@{#30208}