message: fix: dropdown click
diff: @@ -5,6 +5,10 @@ import classNames from 'classnames'
  import Button from '../button/index'
  import Popper from '../popper'
  import Provider from '../context'
  +
  +const ItemWrapper = ({href, children}) => {
  + return href ? <a href={href}>{children}</a> : <React.Fragment>{children}</React.Fragment>
  +}
  class Dropdown extends Component {
  constructor (props) {
  super(props)
  @@ -131,10 +135,6 @@ class Dropdown extends Component {
  String(item.title) === String(title) && 'hi-dropdown__item--active'
  )
  - const ItemWrapper = ({href, children}) => {
  - return href ? <a href={href}>{children}</a> : <React.Fragment>{children}</React.Fragment>
  - }
  -
  return <li className={liCls} key={index} onClick={this.handlerClick.bind(this, item)}>
  <ItemWrapper href={item.url}>
  {(prefix || item.prefix) && <div className='hi-dropdown__item-prefix'>{prefix || item.prefix}</div>}
  