Users: Introduce the `wp_dropdown_users_args` filter, making it possible to filter the arguments for `wp_dropdown_users()` before the query is run.

The 'name' argument (or the `WP_Screen` object if in the admin) can be used to help target specific instances of `wp_dropdown_users()` via this hook.

Props norcross.
See #19867.

Built from https://develop.svn.wordpress.org/trunk@34692


git-svn-id: http://core.svn.wordpress.org/trunk@34656 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/user-functions.php

@@ -922,6 +922,16 @@ function wp_dropdown_users( $args = '' ) {
 
 	$query_args = wp_array_slice_assoc( $r, array( 'blog_id', 'include', 'exclude', 'orderby', 'order', 'who' ) );
 	$query_args['fields'] = array( 'ID', 'user_login', $show );
+
+	/**
+	 * Filter the arguments for user drop-down arguments before being passed into the query.
+	 *
+	 * @since 4.4.0
+	 *
+	 * @param array $query_args The default arguments for wp_dropdown_users().
+	 */
+	$query_args = apply_filters( 'wp_dropdown_users_args', $query_args );
+
 	$users = get_users( $query_args );
 
 	$output = '';

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.4-alpha-34691';
+$wp_version = '4.4-alpha-34692';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.