Return after delete so we don't re-add an empty field.

git-svn-id: http://svn.automattic.com/wordpress/trunk@3666 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/functions.php

@@ -2150,7 +2150,7 @@ function update_usermeta( $user_id, $meta_key, $meta_value ) {
 	$meta_value = trim( $meta_value );
 
 	if (empty($meta_value)) {
-		delete_usermeta($user_id, $meta_key);
+		return delete_usermeta($user_id, $meta_key);
 	}
 
 	$cur = $wpdb->get_row("SELECT * FROM $wpdb->usermeta WHERE user_id = '$user_id' AND meta_key = '$meta_key'");