From 32110c7f77638f83b2e7e7c263e6c225d0b11940 Mon Sep 17 00:00:00 2001
From: Scott Taylor <scott.c.taylor@mac.com>
Date: Sun, 30 Aug 2015 03:01:21 +0000
Subject: [PATCH] Switching themes: if the new theme doesn't have
 `nav_menu_locations` defined, but the old theme does, copy the old theme's
 `nav_menu_locations` into the new theme's theme mods.

cc melchoyce

Fixes #18588.

Built from https://develop.svn.wordpress.org/trunk@33808


git-svn-id: http://core.svn.wordpress.org/trunk@33776 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-includes/theme.php   | 12 ++++++++++++
 wp-includes/version.php |  2 +-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/wp-includes/theme.php b/wp-includes/theme.php
index ae12810961..a9f0e6ed8d 100644
--- a/wp-includes/theme.php
+++ b/wp-includes/theme.php
@@ -688,6 +688,8 @@ function switch_theme( $stylesheet ) {
 		set_theme_mod( 'sidebars_widgets', array( 'time' => time(), 'data' => $_sidebars_widgets ) );
 	}
 
+	$nav_menu_locations = get_theme_mod( 'nav_menu_locations' );
+
 	$old_theme  = wp_get_theme();
 	$new_theme = wp_get_theme( $stylesheet );
 
@@ -716,6 +718,9 @@ function switch_theme( $stylesheet ) {
 	// Migrate from the old mods_{name} option to theme_mods_{slug}.
 	if ( is_admin() && false === get_option( 'theme_mods_' . $stylesheet ) ) {
 		$default_theme_mods = (array) get_option( 'mods_' . $new_name );
+		if ( ! empty( $nav_menu_locations ) && empty( $default_theme_mods['nav_menu_locations'] ) ) {
+			$default_theme_mods['nav_menu_locations'] = $nav_menu_locations;
+		}
 		add_option( "theme_mods_$stylesheet", $default_theme_mods );
 	} else {
 		/*
@@ -726,6 +731,13 @@ function switch_theme( $stylesheet ) {
 		if ( 'wp_ajax_customize_save' === current_action() ) {
 			remove_theme_mod( 'sidebars_widgets' );
 		}
+
+		if ( ! empty( $nav_menu_locations ) ) {
+			$nav_mods = get_theme_mod( 'nav_menu_locations' );
+			if ( empty( $nav_mods ) ) {
+				set_theme_mod( 'nav_menu_locations', $nav_menu_locations );
+			}
+		}
 	}
 
 	update_option( 'theme_switched', $old_theme->get_stylesheet() );
diff --git a/wp-includes/version.php b/wp-includes/version.php
index a8d16b2f97..b454f45983 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.4-alpha-33807';
+$wp_version = '4.4-alpha-33808';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.