Use an explicit boolean has_new_first_party_for_cookies instead...

chrome/browser/renderer_host/resource_dispatcher_host.h

 // Copyright (c) 2009 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.
 
 // This is the browser side of the resource dispatcher, it receives requests
 // from the child process (i.e. [Renderer, Plugin, Worker]ProcessHost), and
 // dispatches them to URLRequests. It then fowards the messages from the
 // URLRequests back to the correct process for handling.
 //
 // See http://dev.chromium.org/developers/design-documents/multi-process-resource-loading
@@ skipping 125 matching lines @@
                      URLRequestContext* request_context);
 
   // Cancels the given request if it still exists. We ignore cancels from the
   // renderer in the event of a download.
   void CancelRequest(int process_unique_id,
                      int request_id,
                      bool from_renderer);
 
   // Follows a deferred redirect for the given request.
   // new_first_party_for_cookies, if non-empty, is the new cookie policy URL
-  // for the redirected URL.  Pass an empty, invalid URL as
-  // new_first_party_for_cookies to indicate that the cookie policy URL
-  // doesn't need changing.
+  // for the redirected URL.  If the cookie policy URL needs changing, pass
+  // true as has_new_first_party_for_cookies and the new cookie policy URL as
+  // new_first_party_for_cookies.  Otherwise, pass false as
+  // has_new_first_party_for_cookies, and new_first_party_for_cookies will not
+  // be used.
   void FollowDeferredRedirect(int process_unique_id,
                               int request_id,
+                              bool has_new_first_party_for_cookies,
                               const GURL& new_first_party_for_cookies);
 
   // Returns true if it's ok to send the data. If there are already too many
   // data messages pending, it pauses the request and returns false. In this
   // case the caller should not send the data.
   bool WillSendData(int process_unique_id, int request_id);
 
   // Pauses or resumes network activity for a particular request.
   void PauseRequest(int process_unique_id, int request_id, bool pause);
 
@@ skipping 238 matching lines @@
                   const ViewHostMsg_Resource_Request& request_data,
                   IPC::Message* sync_result);
   void BeginRequest(int request_id,
                     const ViewHostMsg_Resource_Request& request_data,
                     IPC::Message* sync_result,  // only valid for sync
                     int route_id);  // only valid for async
   void OnDataReceivedACK(int request_id);
   void OnUploadProgressACK(int request_id);
   void OnCancelRequest(int request_id);
   void OnFollowRedirect(int request_id,
+                        bool has_new_first_party_for_cookies,
                         const GURL& new_first_party_for_cookies);
 
   // Returns true if the message passed in is a resource related message.
   static bool IsResourceDispatcherHostMessage(const IPC::Message&);
 
   PendingRequestList pending_requests_;
 
   // A timer that periodically calls UpdateLoadStates while pending_requests_
   // is not empty.
   base::RepeatingTimer<ResourceDispatcherHost> update_load_states_timer_;
@@ skipping 57 matching lines @@
 
   // Keeps track of elements blocked by the Privacy Blacklist.
   chrome::BlockedResponse blocked_;
 
   static bool g_is_http_prioritization_enabled;
 
   DISALLOW_COPY_AND_ASSIGN(ResourceDispatcherHost);
 };
 
 #endif  // CHROME_BROWSER_RENDERER_HOST_RESOURCE_DISPATCHER_HOST_H_