Formatting: Add additional support for single and nestable tags in `force_balance_tags()`.

Adds `track` and `wbr` support for single tags.

Adds `article`, `aside`, `details`, `figure`, and `section` for nestable tags.

Updates tests.

Follow-up to [5805], [21828], [45929].

Props glendaviesnz, costdev, talldanwp, ramonopoly, sergeybiryukov.
Fixes #50225.
Built from https://develop.svn.wordpress.org/trunk@52188


git-svn-id: http://core.svn.wordpress.org/trunk@51780 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/formatting.php

@@ -2514,9 +2514,9 @@ function force_balance_tags( $text ) {
 	$tagqueue  = '';
 	$newtext   = '';
 	// Known single-entity/self-closing tags.
-	$single_tags = array( 'area', 'base', 'basefont', 'br', 'col', 'command', 'embed', 'frame', 'hr', 'img', 'input', 'isindex', 'link', 'meta', 'param', 'source' );
+	$single_tags = array( 'area', 'base', 'basefont', 'br', 'col', 'command', 'embed', 'frame', 'hr', 'img', 'input', 'isindex', 'link', 'meta', 'param', 'source', 'track', 'wbr' );
 	// Tags that can be immediately nested within themselves.
-	$nestable_tags = array( 'blockquote', 'div', 'object', 'q', 'span' );
+	$nestable_tags = array( 'article', 'aside', 'blockquote', 'details', 'div', 'figure', 'object', 'q', 'section', 'span' );
 
 	// WP bug fix for comments - in case you REALLY meant to type '< !--'.
 	$text = str_replace( '< !--', '<    !--', $text );

wp-includes/version.php

@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.9-alpha-52187';
+$wp_version = '5.9-alpha-52188';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.