message: fix(runtime): remove non es5 code from runtime stylesheet
diff: /* eslint-disable no-var */
  import type { Host, StateMap, StateValue } from './types';
  -export function stylesheet(host: Host = {}) {
  +export function stylesheet(host?: Host) {
  + host = host || {};
  var stateMiddleDelimiter = '-';
  var booleanStateDelimiter = '--';
  var stateWithParamDelimiter = '---';
  