Do not create NavigationHandles for inactive RenderFrameHosts

content/browser/frame_host/render_frame_host_impl.cc

Index: content/browser/frame_host/render_frame_host_impl.cc
diff --git a/content/browser/frame_host/render_frame_host_impl.cc b/content/browser/frame_host/render_frame_host_impl.cc
index 1cbc21c45a3e545729ba08a44968c432bd7e456b..3f39d0ebd8bce8068ed06303ce2c4a4a2aba2a89 100644
--- a/content/browser/frame_host/render_frame_host_impl.cc
+++ b/content/browser/frame_host/render_frame_host_impl.cc
@@ -1038,6 +1038,8 @@ void RenderFrameHostImpl::OnDocumentOnLoadCompleted(
 void RenderFrameHostImpl::OnDidStartProvisionalLoad(
     const GURL& url,
     const base::TimeTicks& navigation_start) {
+  if (!is_active())

[nasko, 2016/10/10 20:41:11]

Do we want to add the same to all navigation related methods in RFH? For
example, DidFailProvisionalLoad/DidFailLoad/etc.

[clamy, 2016/10/11 10:34:27]

Added a TODO.

+    return;
   frame_tree_node_->navigator()->DidStartProvisionalLoad(this, url,
                                                          navigation_start);
 }
@@ -1298,13 +1300,8 @@ int RenderFrameHostImpl::GetEnabledBindings() {
 
 void RenderFrameHostImpl::SetNavigationHandle(
     std::unique_ptr<NavigationHandleImpl> navigation_handle) {
+  CHECK(!navigation_handle || is_active());
   navigation_handle_ = std::move(navigation_handle);
-
-  // TODO(clamy): Remove this debug code once we understand better how we get to
-  // the point of attempting to transfer a navigation from a RFH that is no
-  // longer active.
-  if (navigation_handle_ && !is_active())
-    base::debug::DumpWithoutCrashing();

[nasko, 2016/10/10 20:41:10]

Why not keep this around instead of the CHECK, in case there are other cases we
might have missed? We can convert it to a check after few days of bake time, as
crashing the browser process is disruptive.

[clamy, 2016/10/11 10:34:27]

Done.

 }
 
 std::unique_ptr<NavigationHandleImpl>
@@ -1792,6 +1789,8 @@ void RenderFrameHostImpl::OnBeginNavigation(
     const CommonNavigationParams& common_params,
     const BeginNavigationParams& begin_params) {
   CHECK(IsBrowserSideNavigationEnabled());
+  if (!is_active())
+    return;
   CommonNavigationParams validated_params = common_params;
   GetProcess()->FilterURL(false, &validated_params.url);
   frame_tree_node()->navigator()->OnBeginNavigation(