Enforce referrer policies for workers

LayoutTests/http/tests/security/contentSecurityPolicy/resources/worker.php

 <?php
   header("Expires: Thu, 01 Dec 2003 16:00:00 GMT");
   header("Cache-Control: no-cache, must-revalidate");
   header("Pragma: no-cache");
   if ($_GET["csp"]) {
     $csp = $_GET["csp"];
     // If the magic quotes option is enabled, the CSP could be escaped and
     // the test would fail.
     if (get_magic_quotes_gpc()) {
       $csp = stripslashes($csp);
@@ skipping 63 matching lines @@
 }
 postMessage(id === 0 ? "setTimeout blocked" : "setTimeout allowed");
 
 <?php
 } else if ($_GET["type"] == "alert-pass") {
 ?>
 
 alert('PASS');
 
 <?php
+} else if ($_GET["type"] == "report-referrer") {
+?>
+
+var xhr = new XMLHttpRequest;
+xhr.open("GET", "http://127.0.0.1:8000/security/resources/echo-referrer-header.php", true);
+xhr.onload = function () {
+    postMessage(this.responseText);
+};
+xhr.send();
+
+<?php
 }
 ?>