Don't swap out the old RenderFrameHost until the new one commits.

content/browser/cross_site_request_manager.cc

-// 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.
-
-#include "content/browser/cross_site_request_manager.h"
-
-#include "base/memory/singleton.h"
-
-namespace content {
-
-bool CrossSiteRequestManager::HasPendingCrossSiteRequest(int renderer_id,
-                                                         int render_frame_id) {
-  base::AutoLock lock(lock_);
-
-  std::pair<int, int> key(renderer_id, render_frame_id);
-  return pending_cross_site_frames_.find(key) !=
-         pending_cross_site_frames_.end();
-}
-
-void CrossSiteRequestManager::SetHasPendingCrossSiteRequest(int renderer_id,
-                                                            int render_frame_id,
-                                                            bool has_pending) {
-  base::AutoLock lock(lock_);
-
-  std::pair<int, int> key(renderer_id, render_frame_id);
-  if (has_pending) {
-    pending_cross_site_frames_.insert(key);
-  } else {
-    pending_cross_site_frames_.erase(key);
-  }
-}
-
-CrossSiteRequestManager::CrossSiteRequestManager() {}
-
-CrossSiteRequestManager::~CrossSiteRequestManager() {}
-
-// static
-CrossSiteRequestManager* CrossSiteRequestManager::GetInstance() {
-  return Singleton<CrossSiteRequestManager>::get();
-}
-
-}  // namespace content