Twenty Fifteen: keep sub-menus open when visiting sub-menu pages, to show context when navigating a site.

Props jartes, fixes #30722.
Built from https://develop.svn.wordpress.org/trunk@31214


git-svn-id: http://core.svn.wordpress.org/trunk@31195 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-content/themes/twentyfifteen/js/functions.js

@@ -13,6 +13,10 @@
 	// Add dropdown toggle that display child menu items.
 	$( '.main-navigation .menu-item-has-children > a' ).after( '<button class="dropdown-toggle" aria-expanded="false">' + screenReaderText.expand + '</button>' );
 
+	// Toggle buttons and submenu items with active children menu items.
+	$( '.main-navigation .current-menu-ancestor > button' ).addClass( 'toggle-on' );
+	$( '.main-navigation .current-menu-ancestor > .sub-menu' ).addClass( 'toggled-on' );
+
 	$( '.dropdown-toggle' ).click( function( e ) {
 		var _this = $( this );
 		e.preventDefault();

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.2-alpha-31213';
+$wp_version = '4.2-alpha-31214';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.