fix nacl build after r24308

TBR=jarin@chromium.org

BUG=

Review URL: https://codereview.chromium.org/619613002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24312 ce2b1a6d-e550-0410-aec6-3dcde31c8c00