Docs: Improve documentation for some more variadic functions.

Fixes #37402


git-svn-id: https://develop.svn.wordpress.org/trunk@45450 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/includes/dashboard.php

@@ -988,9 +988,10 @@ function wp_dashboard_rss_output( $widget_id ) {
  *
  * @since 2.5.0
  *
- * @param string $widget_id
+ * @param string   $widget_id  The widget ID.
- * @param callable $callback
+ * @param callable $callback   The callback funtion used to display each feed.
- * @param array $check_urls RSS feeds
+ * @param array    $check_urls RSS feeds
+ * @param mixed    ...$args    Optional additional parameters to pass to the callback function when it's called.
  * @return bool False on failure. True on success.
  */
 function wp_dashboard_cached_rss_widget( $widget_id, $callback, $check_urls = array() ) {

src/wp-admin/includes/media.php

@@ -476,15 +476,16 @@ function media_handle_sideload( $file_array, $post_id, $desc = null, $post_data
 }
 
 /**
- * Adds the iframe to display content for the media upload page
+ * Outputs the iframe to display the media upload page.
  *
  * @since 2.5.0
  *
  * @global int $body_id
  *
- * @param string|callable $content_func
+ * @param callable $content_func Function that outputs the content.
+ * @param mixed    ...$args      Optional additional parameters to pass to the callback function when it's called.
  */
-function wp_iframe( $content_func /* ... */ ) {
+function wp_iframe( $content_func ) {
 	_wp_admin_html_begin();
 	?>
 <title><?php bloginfo( 'name' ); ?> &rsaquo; <?php _e( 'Uploads' ); ?> &#8212; <?php _e( 'WordPress' ); ?></title>