This will make it easier to see if the current CPU feature detection
starts breaking because of process sandboxing.

BUG=v8:2597

Review URL: https://chromiumcodereview.appspot.com/13465003
Patch from Hans Wennborg <hans@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@14112 ce2b1a6d-e550-0410-aec6-3dcde31c8c00