This reverts commit r20474 due to an x64 release issue.

R=yangguo@chromium.org

Review URL: https://codereview.chromium.org/223823002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@20478 ce2b1a6d-e550-0410-aec6-3dcde31c8c00