Disable support for swapped out RenderFrame(Host) on desktop.

content/browser/frame_host/frame_tree.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/frame_tree.h"
 
 #include <queue>
 
 #include "base/bind.h"
 #include "base/callback.h"
@@ skipping 281 matching lines @@
   RenderViewHostImpl* rvh = static_cast<RenderViewHostImpl*>(
       RenderViewHostFactory::Create(site_instance,
                                     render_view_delegate_,
                                     render_widget_delegate_,
                                     routing_id,
                                     main_frame_routing_id,
                                     swapped_out,
                                     hidden));
 
   render_view_host_map_[site_instance->GetId()] = rvh;
+  LOG(ERROR) << "FT[" << this << "]::CreateRenderViewHost: "
+    << " created " << rvh << " with refcount:" << rvh->ref_count();
   return rvh;
 }
 
 RenderViewHostImpl* FrameTree::GetRenderViewHost(SiteInstance* site_instance) {
   RenderViewHostMap::iterator iter =
       render_view_host_map_.find(site_instance->GetId());
-  if (iter == render_view_host_map_.end())
+  if (iter == render_view_host_map_.end()) {
+    LOG(ERROR) << "FT[" << this << "]::GetRenderViewHost: "
+      << " could not find RVH for site:"
+      << site_instance->GetId() << "," << site_instance->GetSiteURL();
     return nullptr;
+  }
   return iter->second;
 }
 
 void FrameTree::AddRenderViewHostRef(RenderViewHostImpl* render_view_host) {
   SiteInstance* site_instance = render_view_host->GetSiteInstance();
   RenderViewHostMap::iterator iter =
       render_view_host_map_.find(site_instance->GetId());
   CHECK(iter != render_view_host_map_.end());
   CHECK(iter->second == render_view_host);
 
   iter->second->increment_ref_count();
+  LOG(ERROR) << "FT[" << this << "]::AddRenderViewHostRef: "
+    << iter->second << "|" << iter->second->GetSiteInstance()->GetSiteURL()
+    << " up to " << iter->second->ref_count();
 }
 
 void FrameTree::ReleaseRenderViewHostRef(RenderViewHostImpl* render_view_host) {
   SiteInstance* site_instance = render_view_host->GetSiteInstance();
   int32 site_instance_id = site_instance->GetId();
   RenderViewHostMap::iterator iter =
       render_view_host_map_.find(site_instance_id);
   if (iter != render_view_host_map_.end() && iter->second == render_view_host) {
     // Decrement the refcount and shutdown the RenderViewHost if no one else is
     // using it.
     CHECK_GT(iter->second->ref_count(), 0);
     iter->second->decrement_ref_count();
+    LOG(ERROR) << "FT[" << this << "]::ReleaseRenderViewHostRef: "
+      << iter->second << "|" << iter->second->GetSiteInstance()->GetSiteURL()
+      << " down to " << iter->second->ref_count();
     if (iter->second->ref_count() == 0) {
       iter->second->Shutdown();
       render_view_host_map_.erase(iter);
     }
   } else {
+    LOG(ERROR) << "FT[" << this << "]::ReleaseRenderViewHostRef: "
+      << site_instance_id << " not found in map:" << (iter != render_view_host_map_.end());
+
     // The RenderViewHost should be in the list of RenderViewHosts pending
     // shutdown.
     bool render_view_host_found = false;
     std::pair<RenderViewHostMultiMap::iterator,
               RenderViewHostMultiMap::iterator> result =
         render_view_host_pending_shutdown_map_.equal_range(site_instance_id);
     for (RenderViewHostMultiMap::iterator multi_iter = result.first;
          multi_iter != result.second;
          ++multi_iter) {
       if (multi_iter->second != render_view_host)
@@ skipping 49 matching lines @@
   load_progress_ = 0.0;
 }
 
 bool FrameTree::IsLoading() {
   bool is_loading = false;
   ForEach(base::Bind(&IsNodeLoading, &is_loading));
   return is_loading;
 }
 
 }  // namespace content