Create a new RenderFrameHost per child frame when --site-per-process is enabled.

content/browser/renderer_host/render_frame_host_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/renderer_host/render_frame_host_impl.h"
 
 #include "base/containers/hash_tables.h"
 #include "base/lazy_instance.h"
+#include "content/browser/renderer_host/frame_tree.h"
 #include "content/browser/renderer_host/render_view_host_impl.h"
+#include "content/common/frame_messages.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/render_process_host.h"
 
 namespace content {
 
 // The (process id, routing id) pair that identifies one RenderFrame.
 typedef std::pair<int32, int32> RenderFrameHostID;
 typedef base::hash_map<RenderFrameHostID, RenderFrameHostImpl*>
     RoutingIDFrameMap;
 static base::LazyInstance<RoutingIDFrameMap> g_routing_id_frame_map =
     LAZY_INSTANCE_INITIALIZER;
 
 // static
 RenderFrameHostImpl* RenderFrameHostImpl::FromID(
     int process_id, int routing_id) {
   RoutingIDFrameMap* frames = g_routing_id_frame_map.Pointer();
   RoutingIDFrameMap::iterator it = frames->find(
       RenderFrameHostID(process_id, routing_id));
   return it == frames->end() ? NULL : it->second;
 }
 
 RenderFrameHostImpl::RenderFrameHostImpl(
     RenderViewHostImpl* render_view_host,
+    FrameTree* frame_tree,
     int routing_id,
     bool is_swapped_out)
     : render_view_host_(render_view_host),
+      frame_tree_(frame_tree),
       routing_id_(routing_id),
       is_swapped_out_(is_swapped_out) {
   GetProcess()->AddRoute(routing_id_, this);
   g_routing_id_frame_map.Get().insert(std::make_pair(
       RenderFrameHostID(GetProcess()->GetID(), routing_id_),
       this));
 }
 
 RenderFrameHostImpl::~RenderFrameHostImpl() {
   GetProcess()->RemoveRoute(routing_id_);
   g_routing_id_frame_map.Get().erase(
       RenderFrameHostID(GetProcess()->GetID(), routing_id_));
 
 }
 
 bool RenderFrameHostImpl::Send(IPC::Message* message) {
   return GetProcess()->Send(message);
 }
 
 bool RenderFrameHostImpl::OnMessageReceived(const IPC::Message &msg) {
-  return false;
+  bool handled = true;
+  bool msg_is_ok = true;
+  IPC_BEGIN_MESSAGE_MAP_EX(RenderFrameHostImpl, msg, msg_is_ok)
+    IPC_MESSAGE_HANDLER(FrameHostMsg_Detach, OnDetach)
+  IPC_END_MESSAGE_MAP_EX()
+
+  return handled;
 }
 
 void RenderFrameHostImpl::Init() {
   GetProcess()->ResumeRequestsForView(routing_id());
 }
 
 RenderProcessHost* RenderFrameHostImpl::GetProcess() const {
-  // TODO(ajwong): This should return its own process once cross-process
-  // subframe navigations are supported.
+  // TODO(nasko): This should return its own process, once we have working
+  // cross-process navigation for subframes.
   return render_view_host_->GetProcess();
 }
 
+void RenderFrameHostImpl::OnCreateChildFrame(int new_frame_routing_id,
+                                             int64 parent_frame_id,
+                                             int64 frame_id,
+                                             const std::string& frame_name) {
+  frame_tree_->AddFrame(new_frame_routing_id, parent_frame_id, frame_id,
+                        frame_name);
+}
+
+void RenderFrameHostImpl::OnDetach(int64 parent_frame_id, int64 frame_id) {
+  frame_tree_->RemoveFrame(parent_frame_id, frame_id);
+}
+
 }  // namespace content