Allow query strings for servers in IXR_Client and WP_HTTP_IXR_Client.

props cfinke.
fixes #26947.

Built from https://develop.svn.wordpress.org/trunk@27552


git-svn-id: http://core.svn.wordpress.org/trunk@27395 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/class-IXR.php

@@ -629,6 +629,10 @@ class IXR_Client
             if (!$this->path) {
                 $this->path = '/';
             }
+
+            if ( ! empty( $bits['query'] ) ) {
+                $this->path .= '?' . $bits['query'];
+            }
         } else {
             $this->server = $server;
             $this->path = $path;