Fixing a problem, where a hung renderer process is not killed when navigating away

content/browser/renderer_host/render_view_host_impl.h

Index: content/browser/renderer_host/render_view_host_impl.h
diff --git a/content/browser/renderer_host/render_view_host_impl.h b/content/browser/renderer_host/render_view_host_impl.h
index 8dabcfed3ffa22228640164c94e872a12cd9f690..3dbc67e3f4c674a7a19a0480c881ba99727ce856 100644
--- a/content/browser/renderer_host/render_view_host_impl.h
+++ b/content/browser/renderer_host/render_view_host_impl.h
@@ -283,8 +283,9 @@ class CONTENT_EXPORT RenderViewHostImpl
   // of the parameters.
   void SwapOut(int new_render_process_host_id, int new_request_id);
 
-  // Called by ResourceDispatcherHost after the SwapOutACK is received.
-  void OnSwapOutACK();
+  // Called by ResourceDispatcherHost after the SwapOutACK is received or the
+  // response times out.
+  void OnSwapOutACK(bool timed_out);
 
   // Called to notify the renderer that it has been visibly swapped out and
   // replaced by another RenderViewHost, after an earlier call to SwapOut.
@@ -582,6 +583,9 @@ class CONTENT_EXPORT RenderViewHostImpl
   // is_waiting_for_beforeunload_ack_, unload_ack_is_for_cross_site_transition_.
   bool is_waiting_for_unload_ack_;
 
+  // Set to true when waiting for ViewHostMsg_SwapOut_ACK has timed out.
+  bool has_timed_out_on_unload_;
+
   // Valid only when is_waiting_for_beforeunload_ack_ or
   // is_waiting_for_unload_ack_ is true.  This tells us if the unload request
   // is for closing the entire tab ( = false), or only this RenderViewHost in