function _handleExpandBegin() {
      this.dispatchEvent( 'expandBegin', { target: this } );

      // Set keyboard focus on first menu item link.
      var activeMenuDom = _activeMenu.getDom().content;
      activeMenuDom.classList.remove( 'u-invisible' );
      // TODO: Remove or uncomment when keyboard navigation is in.
      // var firstMenuLink = activeMenuDom.querySelector( 'a' );
      // firstMenuLink.focus();
    }
/**
     * Event handler for when FlyoutMenu expand transition begins.
     * Use this to perform post-expandBegin actions.
     */
Event handler for when FlyoutMenu expand transition begins.
Use this to perform post-expandBegin actions.
Event handler for when FlyoutMenu expand transition begins . Use this to perform post - expandBegin actions .
function _handleExpandBegin() {
      this.dispatchEvent( 'expandBegin', { target: this } );
      var activeMenuDom = _activeMenu.getDom().content;
      activeMenuDom.classList.remove( 'u-invisible' );
    }
function _handleExpandBegin ( ) { this . dispatchEvent ( 'expandBegin' , { target : this } ) ; var activeMenuDom = _activeMenu . getDom ( ) . content ; activeMenuDom . classList . remove ( 'u-invisible' ) ; }
Event handler for when FlyoutMenu expand transition begins.
Event handler for when FlyoutMenu expand transition begins .
// Set keyboard focus on first menu item link. // TODO: Remove or uncomment when keyboard navigation is in. // var firstMenuLink = activeMenuDom.querySelector( 'a' ); // firstMenuLink.focus();