BUG=http://code.google.com/p/v8/issues/detail?id=798
TEST=test/mjsunit/regress/regress-798.js
Review URL: http://codereview.chromium.org/3082012

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5258 ce2b1a6d-e550-0410-aec6-3dcde31c8c00