Ensure RenderViewHost is not shut down until a screenshot of the page is taken.

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 485 matching lines @@
        iter != swapped_out_hosts_.end();
        ++iter) {
     DCHECK_NE(iter->second->GetSiteInstance(),
               current_frame_host()->GetSiteInstance());
     iter->second->render_view_host()->DisownOpener();
   }
 }
 
 void RenderFrameHostManager::RendererProcessClosing(
     RenderProcessHost* render_process_host) {
-  // Remove any swapped out RVHs from this process, so that we don't try to
+  // Remove any swapped out RFHs from this process, so that we don't try to
   // swap them back in while the process is exiting.  Start by finding them,
   // since there could be more than one.
   std::list<int> ids_to_remove;
   for (RenderFrameHostMap::iterator iter = swapped_out_hosts_.begin();
        iter != swapped_out_hosts_.end();
        ++iter) {
     if (iter->second->GetProcess() == render_process_host)
       ids_to_remove.push_back(iter->first);
   }
 
   // Now delete them.
   while (!ids_to_remove.empty()) {
-    delete swapped_out_hosts_[ids_to_remove.back()];
+    RenderFrameHostImpl* rfh = swapped_out_hosts_[ids_to_remove.back()];
+    // The pending RFH may be on the swapped out list if we started to swap it
+    // back in.
+    if (rfh == pending_render_frame_host_.get())
+      CancelPending();
+    else
+      delete swapped_out_hosts_[ids_to_remove.back()];
     swapped_out_hosts_.erase(ids_to_remove.back());
     ids_to_remove.pop_back();
   }
 }
 
 void RenderFrameHostManager::SwapOutOldPage() {
   // Should only see this while we have a pending renderer or transfer.
   CHECK(cross_navigation_pending_ || pending_nav_params_.get());
 
   // Tell the renderer to suppress any further modal dialogs so that we can swap
@@ skipping 933 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