Editor: Use `wp_add_inline_script()` instead of `wp_localize_script()` to pass the `_wpMetaBoxUrl` value to the `wp-editor` script.

This fixes a PHP 8 "Only the first byte will be assigned to the string offset" warning on Edit Post screen.

The correct usage of `wp_localize_script()` is to pass an array of data, not a string.

Fixes #51108.
Built from https://develop.svn.wordpress.org/trunk@48841


git-svn-id: http://core.svn.wordpress.org/trunk@48603 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/edit-form-blocks.php

@@ -125,7 +125,11 @@ $meta_box_url = add_query_arg(
 	),
 	$meta_box_url
 );
-wp_localize_script( 'wp-editor', '_wpMetaBoxUrl', $meta_box_url );
+wp_add_inline_script(
+	'wp-editor',
+	sprintf( 'var _wpMetaBoxUrl = %s;', wp_json_encode( $meta_box_url ) ),
+	'before'
+);
 
 
 /*

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.6-alpha-48840';
+$wp_version = '5.6-alpha-48841';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.