Customize: Allow custom post types to be used in starter content.

Changes `WP_Customize_Nav_Menus::insert_auto_draft_post()` so it can be invoked for a `post_type` that is not registered (yet).

See #38615, #38114.
Fixes #39610.

Built from https://develop.svn.wordpress.org/trunk@39924


git-svn-id: http://core.svn.wordpress.org/trunk@39861 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/class-wp-customize-manager.php

@@ -997,13 +997,19 @@ final class WP_Customize_Manager {
 			wp_list_pluck( $posts, 'post_name' )
 		);
 
+		/*
+		 * Obtain all post types referenced in starter content to use in query.
+		 * This is needed because 'any' will not account for post types not yet registered.
+		 */
+		$post_types = array_filter( array_merge( array( 'attachment' ), wp_list_pluck( $posts, 'post_type' ) ) );
+
 		// Re-use auto-draft starter content posts referenced in the current customized state.
 		$existing_starter_content_posts = array();
 		if ( ! empty( $starter_content_auto_draft_post_ids ) ) {
 			$existing_posts_query = new WP_Query( array(
 				'post__in' => $starter_content_auto_draft_post_ids,
 				'post_status' => 'auto-draft',
-				'post_type' => 'any',
+				'post_type' => $post_types,
 				'posts_per_page' => -1,
 			) );
 			foreach ( $existing_posts_query->posts as $existing_post ) {

wp-includes/class-wp-customize-nav-menus.php

@@ -786,7 +786,7 @@ final class WP_Customize_Nav_Menus {
 	 * @return WP_Post|WP_Error Inserted auto-draft post object or error.
 	 */
 	public function insert_auto_draft_post( $postarr ) {
-		if ( ! isset( $postarr['post_type'] ) || ! post_type_exists( $postarr['post_type'] )  ) {
+		if ( ! isset( $postarr['post_type'] ) ) {
 			return new WP_Error( 'unknown_post_type', __( 'Invalid post type.' ) );
 		}
 		if ( empty( $postarr['post_title'] ) ) {

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.8-alpha-39923';
+$wp_version = '4.8-alpha-39924';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.