The branch delay slot is now utilized in a few loops.
This is the cleanup of an old TODO.

BUG=
TEST=

Review URL: https://chromiumcodereview.appspot.com/9618013

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10949 ce2b1a6d-e550-0410-aec6-3dcde31c8c00