Turn the flag off and see what happens

content/common/swapped_out_messages.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/common/swapped_out_messages.h"
 
 #include "content/common/accessibility_messages.h"
+#include "content/common/frame_messages.h"
 #include "content/common/input_messages.h"
 #include "content/common/view_messages.h"
 #include "content/public/common/content_client.h"
 
 namespace content {
 
 bool SwappedOutMessages::CanSendWhileSwappedOut(const IPC::Message* msg) {
   // We filter out most IPC messages when swapped out.  However, some are
   // important (e.g., ACKs) for keeping the browser and renderer state
   // consistent in case we later return to the same renderer.
@@ skipping 10 matching lines @@
     case ViewHostMsg_ShouldClose_ACK::ID:
     case ViewHostMsg_SwapOut_ACK::ID:
     case ViewHostMsg_ClosePage_ACK::ID:
     case ViewHostMsg_DomOperationResponse::ID:
     case ViewHostMsg_SwapCompositorFrame::ID:
     case ViewHostMsg_UpdateIsDelayed::ID:
     case ViewHostMsg_DidActivateAcceleratedCompositing::ID:
     // Allow cross-process JavaScript calls.
     case ViewHostMsg_RouteCloseEvent::ID:
     case ViewHostMsg_RouteMessageEvent::ID:
+    // Frame detach must occur after the RenderView has swapped out.
+    case FrameHostMsg_Detach::ID:
       return true;
     default:
       break;
   }
 
   // Check with the embedder as well.
   ContentClient* client = GetContentClient();
   return client->CanSendWhileSwappedOut(msg);
 }
 
@@ skipping 37 matching lines @@
     default:
       break;
   }
 
   // Check with the embedder as well.
   ContentClient* client = GetContentClient();
   return client->CanHandleWhileSwappedOut(msg);
 }
 
 }  // namespace content