Fix NavigationControllerBrowserTest.SubframeForwardRedirect

content/browser/frame_host/navigation_request.cc

 // Copyright 2014 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.
 
 #include "content/browser/frame_host/navigation_request.h"
 
 #include <utility>
 
 #include "content/browser/appcache/appcache_navigation_handle.h"
 #include "content/browser/appcache/chrome_appcache_service.h"
@@ skipping 370 matching lines @@
 }
 
 void NavigationRequest::TransferNavigationHandleOwnership(
     RenderFrameHostImpl* render_frame_host) {
   render_frame_host->SetNavigationHandle(std::move(navigation_handle_));
 }
 
 void NavigationRequest::OnRequestRedirected(
     const net::RedirectInfo& redirect_info,
     const scoped_refptr<ResourceResponse>& response) {
+  // If a redirect occurs, the original site instance we thought is the
+  // destination could change.
+  dest_site_instance_ = nullptr;
+
   // If the navigation is no longer a POST, the POST data should be reset.
   if (redirect_info.new_method != "POST")
     common_params_.post_data = nullptr;
 
   // Mark time for the Navigation Timing API.
   if (request_params_.navigation_timing.redirect_start.is_null()) {
     request_params_.navigation_timing.redirect_start =
         request_params_.navigation_timing.fetch_start;
   }
   request_params_.navigation_timing.redirect_end = base::TimeTicks::Now();
@@ skipping 286 matching lines @@
   DCHECK_EQ(request_params_.has_user_gesture, begin_params_.has_user_gesture);
 
   render_frame_host->CommitNavigation(response_.get(), std::move(body_),
                                       common_params_, request_params_,
                                       is_view_source_);
 
   frame_tree_node_->ResetNavigationRequest(true);
 }
 
 }  // namespace content