From 980f342ad6c41b82f6d94a77b9e8ccc541ca1df6 Mon Sep 17 00:00:00 2001
From: Weston Ruter <weston@xwp.co>
Date: Sun, 25 Jun 2017 07:04:42 +0000
Subject: [PATCH] Customize: Ensure `header_image_data` setting exists before
 attempting to use it.

Amends [27497].
Props Collizo4sky.
Fixes #41007.

Built from https://develop.svn.wordpress.org/trunk@40935


git-svn-id: http://core.svn.wordpress.org/trunk@40785 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-admin/custom-header.php | 7 ++++++-
 wp-includes/version.php    | 2 +-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/wp-admin/custom-header.php b/wp-admin/custom-header.php
index b9aecf2485..85238bf21c 100644
--- a/wp-admin/custom-header.php
+++ b/wp-admin/custom-header.php
@@ -1321,7 +1321,12 @@ wp_nonce_field( 'custom-header-options', '_wpnonce-custom-header-options' ); ?>
 	 * @param WP_Customize_Manager $wp_customize Customize manager.
 	 */
 	public function customize_set_last_used( $wp_customize ) {
-		$data = $wp_customize->get_setting( 'header_image_data' )->post_value();
+
+		$header_image_data_setting = $wp_customize->get_setting( 'header_image_data' );
+		if ( ! $header_image_data_setting ) {
+			return;
+		}
+		$data = $header_image_data_setting->post_value();
 
 		if ( ! isset( $data['attachment_id'] ) ) {
 			return;
diff --git a/wp-includes/version.php b/wp-includes/version.php
index c51f719d6f..bc8ff25740 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.9-alpha-40934';
+$wp_version = '4.9-alpha-40935';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.