Taxonomy: Introduce `pre_term_link` filter.

This filter allows developers to filter the taxonomy permalink
structure before a term's permalink is generated. It parallels
the 'pre_post_link' filter for the 'post' post type.

Props nikeo.
Fixes #39601.
Built from https://develop.svn.wordpress.org/trunk@41191


git-svn-id: http://core.svn.wordpress.org/trunk@41031 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/taxonomy.php

@@ -3932,6 +3932,16 @@ function get_term_link( $term, $taxonomy = '' ) {
 
 	$termlink = $wp_rewrite->get_extra_permastruct($taxonomy);
 
+	/**
+	 * Filters the permalink structure for a terms before token replacement occurs.
+	 *
+	 * @since 4.9.0
+	 *
+	 * @param string  $termlink The permalink structure for the term's taxonomy.
+	 * @param WP_Term $term     The term object.
+	 */
+	$termlink = apply_filters( 'pre_term_link', $termlink, $term );
+
 	$slug = $term->slug;
 	$t = get_taxonomy($taxonomy);
 

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.9-alpha-41190';
+$wp_version = '4.9-alpha-41191';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.