Make bleeding edge compile (since r4561 made Handle ctor explicit).  http://codereview.chromium.org/1936001.  Committed for Dmitry Titov of Google

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4570 ce2b1a6d-e550-0410-aec6-3dcde31c8c00