Support frame tree propagation between renderers in the same browsing instance.

content/browser/web_contents/web_contents_impl.cc

 // Copyright (c) 2012 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/web_contents/web_contents_impl.h"
 
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/metrics/histogram.h"
@@ skipping 2728 matching lines @@
 
   // Update the URL display.
   NotifyNavigationStateChanged(content::INVALIDATE_TYPE_URL);
 }
 
 void WebContentsImpl::DidChangeLoadProgress(double progress) {
   if (delegate_)
     delegate_->LoadProgressChanged(this, progress);
 }
 
+void WebContentsImpl::DidUpdateFrameTree(RenderViewHost* rvh) {
+  render_manager_.DidUpdateFrameTree(rvh);
+}
+
 void WebContentsImpl::DocumentAvailableInMainFrame(
     RenderViewHost* render_view_host) {
   FOR_EACH_OBSERVER(WebContentsObserver, observers_,
                     DocumentAvailableInMainFrame());
 }
 
 void WebContentsImpl::DocumentOnLoadCompletedInMainFrame(
     RenderViewHost* render_view_host,
     int32 page_id) {
   content::NotificationService::current()->Notify(
@@ skipping 73 matching lines @@
 
 void WebContentsImpl::RouteMessageEvent(
     RenderViewHost* rvh,
     const ViewMsg_PostMessage_Params& params) {
   // Only deliver the message to the active RenderViewHost if the request
   // came from a RenderViewHost in the same BrowsingInstance.
   if (!rvh->GetSiteInstance()->IsRelatedSiteInstance(GetSiteInstance()))
     return;
 
   ViewMsg_PostMessage_Params new_params(params);
+  RenderViewHost* active_rvh = GetRenderViewHost();
+
+  if (active_rvh->GetProcess()->GetID() != params.target_process_id) {
+    LOG(ERROR) << "Possibly race condition trying to deliver to " <<
+        params.target_process_id << ", which doesn't match " <<
+        active_rvh->GetProcess()->GetID();

[awong, 2012/08/21 19:27:28]

This log isn't going to be seen by anyone. If we need to track this, maybe we
should register a UMA stat (I've never done that before).  Charlie, any
thoughts?

[Charlie Reis, 2012/08/22 22:08:34]

Yeah, I had a similar comment in patch set 10.

+    return;
+  }
+  DCHECK(params.target_frame_id != 0);

[awong, 2012/08/21 19:27:28]

If it is 0, what happens below?

[nasko, 2012/08/21 22:24:13]

0 is an invalid frame ID, so the call won't succeed. We shouldn't be in this
situation though, hence the DCHECK.

 
   // If there is a source_routing_id, translate it to the routing ID for
   // the equivalent swapped out RVH in the target process.  If we need
   // to create a swapped out RVH for the source tab, we create its opener
   // chain as well, since those will also be accessible to the target page.
   if (new_params.source_routing_id != MSG_ROUTING_NONE) {
     // Try to look up the WebContents for the source page.
     WebContentsImpl* source_contents = NULL;
     RenderViewHostImpl* source_rvh = RenderViewHostImpl::FromID(
         rvh->GetProcess()->GetID(), params.source_routing_id);
@@ skipping 359 matching lines @@
       old_browser_plugin_host()->embedder_render_process_host();
   *embedder_container_id = old_browser_plugin_host()->instance_id();
   int embedder_process_id =
       embedder_render_process_host ? embedder_render_process_host->GetID() : -1;
   if (embedder_process_id != -1) {
     *embedder_channel_name =
         StringPrintf("%d.r%d", render_view_host->GetProcess()->GetID(),
                      embedder_process_id);
   }
 }