Rolling v8/build/gyp to 61259d585ce99d9de8b35188cd0025bdbcb58411

Rolling v8/tools/clang to 7f949627a42e2b8b229522ab74de5b1b6a1ced3e

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

Review URL: https://codereview.chromium.org/1768263003

Cr-Commit-Position: refs/heads/master@{#34568}