Revert "Revert 249676 "Have the unload event execute in background on cr...""

content/browser/frame_host/render_frame_host_impl.h

Index: content/browser/frame_host/render_frame_host_impl.h
diff --git a/content/browser/frame_host/render_frame_host_impl.h b/content/browser/frame_host/render_frame_host_impl.h
index cf58b878d77cc4763f8b7d44c7660374f20dc171..12a0059b0a9e049f4d4735fc67948ba52ed53afe 100644
--- a/content/browser/frame_host/render_frame_host_impl.h
+++ b/content/browser/frame_host/render_frame_host_impl.h
@@ -7,6 +7,7 @@
 
 #include <string>
 
+#include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/strings/string16.h"
 #include "content/common/content_export.h"
@@ -82,6 +83,10 @@ class CONTENT_EXPORT RenderFrameHostImpl : public RenderFrameHost {
     is_swapped_out_ = is_swapped_out;
   }
 
+  // Sets the RVH for |this| as pending shutdown. |on_swap_out| will be called
+  // when the SwapOutACK is received.
+  void SetPendingShutdown(const base::Closure& on_swap_out);
+
   // TODO(nasko): This method is public so RenderViewHostImpl::Navigate can
   // call it directly. It should be made private once Navigate moves here.
   void OnDidStartLoading();