This patch avoid to push some values on the stack when it's not needed.

R=ulan@chromium.org

Review URL: https://codereview.chromium.org/183193005

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19708 ce2b1a6d-e550-0410-aec6-3dcde31c8c00