Blink uses three slots, so instead of having to reallocate the array
everytime, make it big enough to begin with.

BUG=none
LOG=n
R=svenpanne@chromium.org

Review URL: https://codereview.chromium.org/109953004

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@18335 ce2b1a6d-e550-0410-aec6-3dcde31c8c00