Also rip out the unused runtime-unittests; will be added back on-demand.

BUG=v8:3489
LOG=n
R=ulan@chromium.org, svenpanne@chromium.org

Review URL: https://codereview.chromium.org/525193004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23545 ce2b1a6d-e550-0410-aec6-3dcde31c8c00