Move JSON-stringify webkit test to V8.

BUG=367089
LOG=N
R=machenbach@chromium.org

Review URL: https://codereview.chromium.org/254673005

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@20977 ce2b1a6d-e550-0410-aec6-3dcde31c8c00