Restore virtual test suites accidentally dropped in r159429.

TBR=ojan@chromium.org
BUG=304428

Review URL: https://codereview.chromium.org/26741002

git-svn-id: svn://svn.chromium.org/blink/trunk@159253 bbb929c8-8fbe-4397-9dbb-9b2b20218538