Bug 401564 - Test and fix for redirection losing Accept header. r=mcmanus

The test has a redirect where the initial GET request had Accept:
application/json, and ensures that this is also the type of the
redirected request.

The fix is done in the setup of the replicated HttpBaseChannel, where
the previous channel's Accept header is copied to the new one, if it
exists.

netwerk/protocol/http/HttpBaseChannel.cpp

@@ -1810,6 +1810,17 @@ HttpBaseChannel::SetupReplacementChannel(nsIURI       *newURI,
   // convey the new redirection limit
   httpChannel->SetRedirectionLimit(mRedirectionLimit - 1);
 
+  // convey the Accept header value
+  {
+    nsAutoCString oldAcceptValue;
+    nsresult hasHeader = mRequestHead.GetHeader(nsHttp::Accept, oldAcceptValue);
+    if (NS_SUCCEEDED(hasHeader)) {
+      httpChannel->SetRequestHeader(NS_LITERAL_CSTRING("Accept"),
+                                    oldAcceptValue,
+                                    false);
+    }
+  }
+
   nsCOMPtr<nsIHttpChannelInternal> httpInternal = do_QueryInterface(newChannel);
   if (httpInternal) {
     // convey the mForceAllowThirdPartyCookie flag

netwerk/test/unit/test_bug401564.js

@@ -0,0 +1,49 @@
+/* -*- Mode: JavaScript; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+"use strict";
+Cu.import("resource://testing-common/httpd.js");
+
+var httpserver = null;
+const noRedirectURI = "/content";
+const pageValue = "Final page";
+const acceptType = "application/json";
+
+function redirectHandler(metadata, response)
+{
+  response.setStatusLine(metadata.httpVersion, 302, "Moved Temporarily");
+  response.setHeader("Location", noRedirectURI, false);
+}
+
+function contentHandler(metadata, response)
+{
+  do_check_eq(metadata.getHeader("Accept"), acceptType);
+  httpserver.stop(do_test_finished);
+}
+
+function dummyHandler(request, buffer)
+{
+}
+
+function run_test()
+{
+  httpserver = new HttpServer();
+  httpserver.registerPathHandler("/redirect", redirectHandler);
+  httpserver.registerPathHandler("/content", contentHandler);
+  httpserver.start(-1);
+
+  var prefs = Cc["@mozilla.org/preferences-service;1"]
+                .getService(Components.interfaces.nsIPrefBranch);
+  prefs.setBoolPref("network.http.prompt-temp-redirect", false);
+
+  var ios = Cc["@mozilla.org/network/io-service;1"].getService(Ci.nsIIOService);
+  var chan = ios.newChannel("http://localhost:" +
+                            httpserver.identity.primaryPort + "/redirect",
+                            "",
+                            null);
+
+  chan.QueryInterface(Ci.nsIHttpChannel);
+  chan.setRequestHeader("Accept", acceptType, false);
+
+  chan.asyncOpen(new ChannelListener(dummyHandler, null), null);
+
+  do_test_pending();
+}

netwerk/test/unit/xpcshell.ini

@@ -96,6 +96,7 @@ skip-if = "FTP channel implementation needs to migrate to the new cache backend
 [test_bug380994.js]
 [test_bug388281.js]
 [test_bug396389.js]
+[test_bug401564.js]
 [test_bug411952.js]
 [test_bug412945.js]
 [test_bug414122.js]