Minor cleanup of GVN state pushing.

R=hpayer@chromium.org, hpayer@google.com

Review URL: https://codereview.chromium.org/19235010

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@15685 ce2b1a6d-e550-0410-aec6-3dcde31c8c00