and "Win64 fix for r19833."

This reverts commits r19833 and r19837 for breaking Windows tests
(test-api/PersistentValueMap).

TBR=vogelheim@chromium.org,dcarney@chromium.org

Review URL: https://codereview.chromium.org/197173002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19839 ce2b1a6d-e550-0410-aec6-3dcde31c8c00