Allow RenderFrames to swap out for subframe navigations.

content/browser/frame_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/frame_host/render_frame_host_impl.h"
 
 #include "base/containers/hash_tables.h"
 #include "base/lazy_instance.h"
 #include "content/browser/frame_host/frame_tree.h"
 #include "content/browser/frame_host/frame_tree_node.h"
@@ skipping 79 matching lines @@
 bool RenderFrameHostImpl::OnMessageReceived(const IPC::Message &msg) {
   if (delegate_->OnMessageReceived(this, msg))
     return true;
 
   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_MESSAGE_HANDLER(FrameHostMsg_DidStartProvisionalLoadForFrame,
                         OnDidStartProvisionalLoadForFrame)
+    IPC_MESSAGE_HANDLER(FrameHostMsg_SwapOut_ACK, OnSwapOutACK)
   IPC_END_MESSAGE_MAP_EX()
 
   if (!msg_is_ok) {
     // The message had a handler, but its de-serialization failed.
     // Kill the renderer.
     RecordAction(UserMetricsAction("BadMessageTerminate_RFH"));
     GetProcess()->ReceivedBadMessage();
   }
 
   return handled;
@@ skipping 19 matching lines @@
 
 void RenderFrameHostImpl::OnDidStartProvisionalLoadForFrame(
     int64 frame_id,
     int64 parent_frame_id,
     bool is_main_frame,
     const GURL& url) {
   frame_tree_node_->navigator()->DidStartProvisionalLoad(
       this, frame_id, parent_frame_id, is_main_frame, url);
 }
 
+void RenderFrameHostImpl::SwapOut() {
+  if (render_view_host_->IsRenderViewLive()) {
+    Send(new FrameMsg_SwapOut(routing_id()));
+  } else {
+    // Our RenderViewHost doesn't have a live renderer, so just skip the unload
+    // event.
+    OnSwappedOut(true);
+  }
+}
+
+void RenderFrameHostImpl::OnSwapOutACK() {
+  OnSwappedOut(false);
+}
+
+void RenderFrameHostImpl::OnSwappedOut(bool timed_out) {
+  frame_tree_node_->render_manager()->SwappedOutFrame(this);
+}
+
 }  // namespace content