Add fake headers to URLRequestRedirectJobs.

chrome/test/data/extensions/api_test/webrequest/test_blocking.js

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 var pass = chrome.test.callbackPass;
 
 // Constants as functions, not to be called until after runTests.
 function getURLEchoUserAgent() {
   return getServerURL('echoheader?User-Agent');
 }
@@ skipping 262 matching lines @@
             url: getURL("complexLoad/a.html"),
             frameUrl: getURL("complexLoad/a.html")
           },
           retval: {redirectUrl: getURL("simpleLoad/a.html")}
         },
         { label: "onBeforeRedirect",
           event: "onBeforeRedirect",
           details: {
             url: getURL("complexLoad/a.html"),
             redirectUrl: getURL("simpleLoad/a.html"),
-            statusLine: "",
-            statusCode: -1,
             fromCache: false,
+            statusLine: "HTTP/1.1 307 Internal Redirect",
+            statusCode: 307,
           }
         },
         { label: "onBeforeRequest-2",
           event: "onBeforeRequest",
           details: {
             url: getURL("simpleLoad/a.html"),
             frameUrl: getURL("simpleLoad/a.html"),
           },
         },
         { label: "onResponseStarted",
@@ skipping 691 matching lines @@
     // Check the page content for our modified User-Agent string.
     navigateAndWait(getURL("simpleLoad/a.html"), function() {
         var req = new XMLHttpRequest();
         var asynchronous = true;
         req.open("GET", getURLHttpXHRData(), asynchronous);
         req.send(null);
         navigateAndWait(getURL("complexLoad/b.jpg"));
     });
   },
 ]);