Add ref-count on RenderViewHost for each new RenderFrameProxyHost.

content/browser/frame_host/render_frame_proxy_host.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/render_frame_proxy_host.h"
 
 #include "base/lazy_instance.h"
 #include "content/browser/bad_message.h"
 #include "content/browser/frame_host/cross_process_frame_connector.h"
 #include "content/browser/frame_host/frame_tree.h"
@@ skipping 26 matching lines @@
 RenderFrameProxyHost* RenderFrameProxyHost::FromID(int process_id,
                                                    int routing_id) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
   RoutingIDFrameProxyMap* frames = g_routing_id_frame_proxy_map.Pointer();
   RoutingIDFrameProxyMap::iterator it = frames->find(
       RenderFrameProxyHostID(process_id, routing_id));
   return it == frames->end() ? NULL : it->second;
 }
 
 RenderFrameProxyHost::RenderFrameProxyHost(SiteInstance* site_instance,
+                                           RenderViewHostImpl* render_view_host,
                                            FrameTreeNode* frame_tree_node)
     : routing_id_(site_instance->GetProcess()->GetNextRoutingID()),
       site_instance_(site_instance),
       process_(site_instance->GetProcess()),
       frame_tree_node_(frame_tree_node),
-      render_frame_proxy_created_(false) {
+      render_frame_proxy_created_(false),
+      render_view_host_(render_view_host) {
   GetProcess()->AddRoute(routing_id_, this);
   CHECK(g_routing_id_frame_proxy_map.Get().insert(
       std::make_pair(
           RenderFrameProxyHostID(GetProcess()->GetID(), routing_id_),
           this)).second);
+  frame_tree_node_->frame_tree()->RegisterRenderViewHost(render_view_host_);

[Charlie Reis, 2015/05/20 23:05:00]

Should we check that render_view_host is non-null, either here or in the
register call?  (I mention it because of the possible issue in RFHM.)

[nasko, 2015/05/21 16:22:12]

I can add a CHECK if you'd prefer, but we shouldn't be getting a null RVH.

[Charlie Reis, 2015/05/21 18:48:16]

Yeah, let's put a CHECK here.  I'd like to know if this invariant fails in
practice, especially since we store it in a map.

[nasko, 2015/05/21 21:37:07]

Done.

 
   if (!frame_tree_node_->IsMainFrame() &&
       frame_tree_node_->parent()
               ->render_manager()
               ->current_frame_host()
               ->GetSiteInstance() == site_instance) {
     // The RenderFrameHost navigating cross-process is destroyed and a proxy for
     // it is created in the parent's process. CrossProcessFrameConnector
     // initialization only needs to happen on an initial cross-process
     // navigation, when the RenderFrameHost leaves the same process as its
     // parent. The same CrossProcessFrameConnector is used for subsequent cross-
     // process navigations, but it will be destroyed if the frame is
     // navigated back to the same SiteInstance as its parent.
     cross_process_frame_connector_.reset(new CrossProcessFrameConnector(this));
   }
 }
 
 RenderFrameProxyHost::~RenderFrameProxyHost() {
   if (GetProcess()->HasConnection()) {
     // TODO(nasko): For now, don't send this IPC for top-level frames, as
     // the top-level RenderFrame will delete the RenderFrameProxy.
     // This can be removed once we don't have a swapped out state on
     // RenderFrame. See https://crbug.com/357747
     if (!frame_tree_node_->IsMainFrame())
       Send(new FrameMsg_DeleteProxy(routing_id_));
   }
 
+  frame_tree_node_->frame_tree()->UnregisterRenderViewHost(render_view_host_);
   GetProcess()->RemoveRoute(routing_id_);
   g_routing_id_frame_proxy_map.Get().erase(
       RenderFrameProxyHostID(GetProcess()->GetID(), routing_id_));
 }
 
 void RenderFrameProxyHost::SetChildRWHView(RenderWidgetHostView* view) {
   cross_process_frame_connector_->set_view(
       static_cast<RenderWidgetHostViewChildFrame*>(view));
 }
 
@@ skipping 173 matching lines @@
         base::Bind(&MessagePortMessageFilter::RouteMessageEventWithMessagePorts,
                    message_port_message_filter, target_rfh->GetRoutingID(),
                    new_params));
   } else {
     target_rfh->Send(
         new FrameMsg_PostMessageEvent(target_rfh->GetRoutingID(), new_params));
   }
 }
 
 }  // namespace content