Adding a menu toggle for a third menu item

gistfile1.txt

/**
 * navigation.js
 *
 * Handles toggling the navigation menu for small screens and enables tab
 * support for dropdown menus.
 */
( function() {
	var tertiary_container, tertiary_button, tertiary_menu, tertiary_links, tertiary_subMenus;

	tertiary_container = document.getElementById( 'tertiary-navigation' );
	if ( ! tertiary_container ) {
		return;
	}

	tertiary_button = tertiary_container.querySelector('.tertiary-menu-toggle');
	if ( 'undefined' === typeof tertiary_button ) {
		return;
	}

	tertiary_menu = tertiary_container.getElementsByTagName( 'ul' )[0];

	// Hide menu toggle button if menu is empty and return early.
	if ( 'undefined' === typeof tertiary_menu ) {
		tertiary_button.style.display = 'none';
		return;
	}

	tertiary_menu.setAttribute( 'aria-expanded', 'false' );
	if ( -1 === tertiary_menu.className.indexOf( 'nav-menu' ) ) {
		tertiary_menu.className += ' nav-menu';
	}

	tertiary_button.onclick = function() {
		if ( -1 !== tertiary_container.className.indexOf( 'toggled' ) ) {
			tertiary_container.className = tertiary_container.className.replace( ' toggled', '' );
			tertiary_button.setAttribute( 'aria-expanded', 'false' );
			tertiary_menu.setAttribute( 'aria-expanded', 'false' );
		} else {
			tertiary_container.className += ' toggled';
			tertiary_button.setAttribute( 'aria-expanded', 'true' );
			tertiary_menu.setAttribute( 'aria-expanded', 'true' );
		}
	};

	// Get all the link elements within the menu.
	tertiary_links    = tertiary_menu.getElementsByTagName( 'a' );
	tertiary_subMenus = tertiary_menu.getElementsByTagName( 'ul' );

	// Set menu items with submenus to aria-haspopup="true".
	for ( var i = 0, len = tertiary_subMenus.length; i < len; i++ ) {
		tertiary_subMenus[i].parentNode.setAttribute( 'aria-haspopup', 'true' );
	}

	// Each time a menu link is focused or blurred, toggle focus.
	for ( i = 0, len = tertiary_links.length; i < len; i++ ) {
		tertiary_links[i].addEventListener( 'focus', toggleFocus, true );
		tertiary_links[i].addEventListener( 'blur', toggleFocus, true );
	}

	/**
	 * Sets or removes .focus class on an element.
	 */
	function toggleFocus() {
		var tertiary_self = this;

		// Move up through the ancestors of the current link until we hit .nav-menu.
		while ( -1 === tertiary_self.className.indexOf( 'nav-menu' ) ) {

			// On li elements toggle the class .focus.
			if ( 'li' === tertiary_self.tagName.toLowerCase() ) {
				if ( -1 !== tertiary_self.className.indexOf( 'focus' ) ) {
					tertiary_self.className = tertiary_self.className.replace( ' focus', '' );
				} else {
					tertiary_self.className += ' focus';
				}
			}

			tertiary_self = tertiary_self.parentElement;
		}
	}
} )();

jQuery(window).load(function($) {
	
	// Add dropdown toggle that display child menu items.
	jQuery( '.tertiary-navigation .page_item_has_children > a, .tertiary-navigation .menu-item-has-children > a' ).after( '<a href="#" class="dropdown-toggle" aria-expanded="false"><i class="fa fa-caret-down"></i></a>' );

});