Allow redirects for requests that require preflight.

third_party/WebKit/LayoutTests/http/tests/serviceworker/resources/fetch-access-control.php

 <?php
 header('X-ServiceWorker-ServerHeader: SetInTheServer');
 
 $prefix = '';
 // If PreflightTest is set:
 // - Use PACAOrign, PACAHeaders, PACAMethods, PACACredentials, PACEHeaders,
 //   PAuth, PAuthFail and PSetCookie* parameters in preflight.
 // - Use $_GET['PreflightTest'] as HTTP status code.
 // - Check Access-Control-Request-Method/Headers headers with
 //   PACRMethod/Headers parameter, if set, in preflight.
@@ skipping 13 matching lines @@
         exit;
     }
     // Preflight must not include Cookie headers.
     if (isset($_SERVER['HTTP_COOKIE'])) {
         header("HTTP/1.1 400");
         exit;
     }
     header("HTTP/1.1 {$_GET['PreflightTest']}");
 }
 
+if (isset($_GET['Redirect'])) {
+    if (isset($_GET['Status'])) {
+        header("HTTP/1.1 $_GET[Status]");
+    } else {
+        header('HTTP/1.1 302');
+    }
+    $url = $_GET['Redirect'];
+    if ($url !== 'noLocation') {
+        header("Location: $url");
+    }
+}
 if (isset($_GET[$prefix . 'ACAOrigin'])) {
     $origins = explode(',', $_GET[$prefix . 'ACAOrigin']);
     for ($i = 0; $i < sizeof($origins); ++$i)
         header("Access-Control-Allow-Origin: " . $origins[$i], false);
 }
 if (isset($_GET[$prefix . 'ACAHeaders']))
     header('Access-Control-Allow-Headers: ' . $_GET[$prefix . 'ACAHeaders']);
 if (isset($_GET[$prefix . 'ACAMethods']))
     header('Access-Control-Allow-Methods: ' . $_GET[$prefix . 'ACAMethods']);
 if (isset($_GET[$prefix . 'ACACredentials']))
@@ skipping 58 matching lines @@
              'headers' => getallheaders(),
              'body' => file_get_contents('php://input'),
              'files' => $files,
              'get' => $_GET,
              'post' => $_POST,
              'username' => $username,
              'password' => $password,
              'cookie' => $cookie);
 $json = json_encode($arr);
 echo "report( $json );";
-?>
+?>