Add test for filtering of IPC messages when RenderFrameHost is swapped out.

content/browser/frame_host/render_frame_host_manager.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_manager.h"
 
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
@@ skipping 450 matching lines @@
     // Even when there is no pending RVH, there may be a pending Web UI.
     if (pending_web_ui())
       CommitPending();
     return;
   }
 
   if (render_view_host == pending_render_frame_host_->render_view_host()) {
     // The pending cross-site navigation completed, so show the renderer.
     // If it committed without sending network requests (e.g., data URLs),
     // then we still need to swap out the old RFH first and run its unload
-    // handler.  OK for that to happen in the background.
+    // handler.  OK for that to happen in the background, only if it hasn't
+    // happened yet.

[Charlie Reis, 2014/03/21 21:35:13]

Please move "if it hasn't happened yet" to the end of the previous sentence,
since it's about whether we need to run the unload handler, not whether it runs
in the background.

[nasko, 2014/03/24 17:48:11]

Done.

     if (pending_render_frame_host_->render_view_host()->
-            HasPendingCrossSiteRequest())
+            HasPendingCrossSiteRequest() &&
+        pending_render_frame_host_->render_view_host()->rvh_state() !=
+            RenderViewHostImpl::STATE_WAITING_FOR_COMMIT) {

[Charlie Reis, 2014/03/21 21:35:13]

What if it were STATE_WAITING_FOR_UNLOAD_ACK?  That means we've already called
SwapOut and don't need to again.  Presumably the same thing for PENDING_SWAP_OUT
and PENDING_SHUTDOWN, right?

Should this check be rvh_state() == STATE_DEFAULT?

(Edit: I think so, since that's what we're checking for in RVHI::SwapOut.)

[nasko, 2014/03/24 17:48:11]

Done.

       SwapOutOldPage();
+    }
 
     CommitPending();
     cross_navigation_pending_ = false;
   } else if (render_view_host == render_frame_host_->render_view_host()) {
     // A navigation in the original page has taken place.  Cancel the pending
     // one.
     CancelPending();
     cross_navigation_pending_ = false;
   } else {
     // No one else should be sending us DidNavigate in this state.
@@ skipping 978 matching lines @@
     SiteInstance* instance) const {
   RenderFrameHostMap::const_iterator iter =
       swapped_out_hosts_.find(instance->GetId());
   if (iter != swapped_out_hosts_.end())
     return iter->second;
 
   return NULL;
 }
 
 }  // namespace content