make MacOS compiler happier.

We need to clean this stuff up.

TBR=whesse@chromium.org
Review URL: http://codereview.chromium.org/182044

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2802 ce2b1a6d-e550-0410-aec6-3dcde31c8c00