message: Always set dropdownWidth dropdown not visible
  setState will stop animation when visible change to true at first time
diff: @@ -58,14 +58,11 @@ export default class SelectTrigger extends React.Component {
  }
  setDropdownWidth = () => {
  - const { visible } = this.props;
  - if (visible) {
  const width = ReactDOM.findDOMNode(this).offsetWidth;
  if (width !== this.state.dropdownWidth) {
  this.setState({ dropdownWidth: width });
  }
  }
  - }
  getInnerMenu = () => {
  return this.popupMenu && this.popupMenu.refs.menu;
  