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

content/browser/frame_host/render_frame_host_manager.cc

Index: content/browser/frame_host/render_frame_host_manager.cc
diff --git a/content/browser/frame_host/render_frame_host_manager.cc b/content/browser/frame_host/render_frame_host_manager.cc
index 791eb89285c912ad392802815b6a6b94c6214be6..116ea68a667a33c205a8989f3244bce09ee43706 100644
--- a/content/browser/frame_host/render_frame_host_manager.cc
+++ b/content/browser/frame_host/render_frame_host_manager.cc
@@ -503,7 +503,7 @@ void RenderFrameHostManager::DidDisownOpener(RenderViewHost* render_view_host) {
 
 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;
@@ -516,7 +516,13 @@ void RenderFrameHostManager::RendererProcessClosing(
 
   // 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();
   }