docs: function prefixed(obj, property) {
    var prefix;
    var prop;
    var camelProp = property[0].toUpperCase() + property.slice(1);
  
    var i = 0;
    while (i < VENDOR_PREFIXES.length) {
      prefix = VENDOR_PREFIXES[i];
      prop = (prefix) ? prefix + camelProp : property;
  
      if (prop in obj) {
        return prop;
      }
      i++;
    }
    return undefined;
  }