seeds.  This change is performance neutral on most snapshot
VM builds, but provides a big improvement on string-fasta
on around 5% of builds.
Review URL: https://chromiumcodereview.appspot.com/9193015

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10478 ce2b1a6d-e550-0410-aec6-3dcde31c8c00