This reverts commit r20146 which broke V8 GC Stress, Mjsunit tests.

R=yangguo@chromium.org

Review URL: https://codereview.chromium.org/207963002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@20154 ce2b1a6d-e550-0410-aec6-3dcde31c8c00