Index: src/wp-admin/includes/ajax-actions.php
===================================================================
--- src/wp-admin/includes/ajax-actions.php	(revision 45721)
+++ src/wp-admin/includes/ajax-actions.php	(working copy)
@@ -149,10 +149,10 @@
 	if ( ( $term_search_min_chars == 0 ) || ( strlen( $s ) < $term_search_min_chars ) ) {
 		wp_die();
 	}
-
+	
 	$results = get_terms(
-		$taxonomy,
 		array(
+			'taxonomy' => $taxonomy,
 			'name__like' => $s,
 			'fields'     => 'names',
 			'hide_empty' => false,