PlzNavigate: Cancel ongoing history navigations in the browser when we receive a navigation request…

content/browser/frame_host/navigator_impl.cc

 // Copyright 2013 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/navigator_impl.h"
 
 #include <utility>
 
 #include "base/logging.h"
 #include "base/metrics/histogram_macros.h"
@@ skipping 980 matching lines @@
     const BeginNavigationParams& begin_params) {
   // TODO(clamy): the url sent by the renderer should be validated with
   // FilterURL.
   // This is a renderer-initiated navigation.
   CHECK(IsBrowserSideNavigationEnabled());
   DCHECK(frame_tree_node);
 
   NavigationRequest* ongoing_navigation_request =
       frame_tree_node->navigation_request();
 
+  // Client redirects during the initial history navigation of a child frame
+  // should take precedence over the history navigation (despite being renderer-
+  // initiated).  See https://crbug.com/348447 and https://crbug.com/691168.
+  if (ongoing_navigation_request &&
+      ongoing_navigation_request->request_params()
+          .is_history_navigation_in_new_child) {
+    // Preemptively clear this local pointer before deleting the request.
+    ongoing_navigation_request = nullptr;
+    frame_tree_node->ResetNavigationRequest(false);
+  }
+
   // The renderer-initiated navigation request is ignored iff a) there is an
   // ongoing request b) which is browser or user-initiated and c) the renderer
   // request is not user-initiated.
   if (ongoing_navigation_request &&
       (ongoing_navigation_request->browser_initiated() ||
        ongoing_navigation_request->begin_params().has_user_gesture) &&
       !begin_params.has_user_gesture) {
     RenderFrameHost* current_frame_host =
         frame_tree_node->render_manager()->current_frame_host();
     current_frame_host->Send(
@@ skipping 193 matching lines @@
   frame_tree_node->navigation_request()->CreateNavigationHandle(
       entry.GetUniqueID());
 
   NavigationRequest* navigation_request = frame_tree_node->navigation_request();
   if (!navigation_request)
     return;  // Navigation was synchronously stopped.
 
   // Have the current renderer execute its beforeunload event if needed. If it
   // is not needed then NavigationRequest::BeginNavigation should be directly
   // called instead.
-  if (should_dispatch_beforeunload && !IsRendererDebugURL(dest_url)) {
+  // We don't want to dispatch a beforeunload handler if
+  // is_history_navigation_in_new_child is true. This indicates a newly created
+  // child frame which does not have a beforunload handler.
+  if (should_dispatch_beforeunload && !IsRendererDebugURL(dest_url) &&
+      !is_history_navigation_in_new_child) {

[Charlie Reis, 2017/02/18 00:22:52]

Oh, sorry!  I meant 1 line up from where it was, on 1185 (now 1182).

[ananta, 2017/02/18 00:32:05]

Done.

     navigation_request->SetWaitingForRendererResponse();
     frame_tree_node->current_frame_host()->DispatchBeforeUnload(
         true, reload_type != ReloadType::NONE);
   } else {
     navigation_request->BeginNavigation();
   }
 }
 
 void NavigatorImpl::RecordNavigationMetrics(
     const LoadCommittedDetails& details,
@@ skipping 96 matching lines @@
     if (navigation_handle)
       navigation_handle->update_entry_id_for_transfer(entry->GetUniqueID());
 
     controller_->SetPendingEntry(std::move(entry));
     if (delegate_)
       delegate_->NotifyChangedNavigationState(content::INVALIDATE_TYPE_URL);
   }
 }
 
 }  // namespace content