analytics.js
function variation(id) {
  var experiments = window._vwo_exp;
  if (!experiments) return null;
  var experiment = experiments[id];
  var variationId = experiment.combination_chosen;
  return variationId ? experiment.comb_n[variationId] : null;
}
function variation(id) {
  var experiments = window._vwo_exp;
  if (!experiments) return null;
  var experiment = experiments[id];
  var variationId = experiment.combination_chosen;
  return variationId ? experiment.comb_n[variationId] : null;
}
function variation ( id ) { var experiments = window . _vwo_exp ; if ( ! experiments ) return null ; var experiment = experiments [ id ] ; var variationId = experiment . combination_chosen ; return variationId ? experiment . comb_n [ variationId ] : null ; }
Get the chosen variation's name from an experiment `id`.

http://visualwebsiteoptimizer.com/knowledge/integration-of-vwo-with-kissmetrics/

@param {String} id
@return {String}
Get the chosen variation s name from an experiment id .