message: Add test to Select.combobox.spec.js as well
diff: @@ -6,11 +6,13 @@ import KeyCode from 'rc-util/lib/KeyCode';
  import allowClearTest from './shared/allowClearTest';
  import throwOptionValue from './shared/throwOptionValue';
  import focusTest from './shared/focusTest';
  +import keyDownTest from './shared/keyDownTest';
  describe('Select.combobox', () => {
  allowClearTest('combobox');
  throwOptionValue('combobox');
  focusTest('combobox');
  + keyDownTest('combobox');
  it('renders correctly', () => {
  const wrapper = render(
  