Have the unload event execute in background on cross-site navigations

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 44851eea0e2983c78abd680af49322e2b72a555b..909e5714e2100f4a1757f50e182d8eb0d90bea0f 100644
--- a/content/browser/renderer_host/render_view_host_impl.h
+++ b/content/browser/renderer_host/render_view_host_impl.h
@@ -295,6 +295,20 @@ class CONTENT_EXPORT RenderViewHostImpl
   // different process.
   bool is_swapped_out() const { return is_swapped_out_; }
 
+  // Whether this RenderViewHost is waiting for the execution of the unload in
+  // the background, and should not be destroyed on SwapOut, even if it was the
+  // last active in the SiteInstance.
+  bool should_be_preserved_on_swap_out() const {

[Charlie Reis, 2013/12/09 20:12:29]

I don't think we need these.

+    return should_be_preserved_on_swap_out_;
+  }
+
+  // Whether this RenderViewHostImpl needs to perform additional cleanup before
+  // being deleted. This is the case if the renderer was left to execute the
+  // unload event in the background.
+  bool need_to_perform_clean_up_on_swapped_out() const {
+    return need_to_perform_clean_up_on_swapped_out_;
+  }
+
   // Called on the pending RenderViewHost when the network response is ready to
   // commit.  We should ensure that the old RenderViewHost runs its unload
   // handler and determine whether a transfer to a different RenderViewHost is
@@ -324,7 +338,7 @@ class CONTENT_EXPORT RenderViewHostImpl
 
   // Called when either the SwapOut request has been acknowledged or has timed
   // out.
-  void OnSwappedOut(bool timed_out);
+  void OnSwappedOut(bool timed_out, bool preserve_render_view_host);

[Charlie Reis, 2013/12/09 20:12:29]

I think we can get rid of this whole method.

 
   // Called to notify the renderer that it has been visibly swapped out and
   // replaced by another RenderViewHost, after an earlier call to SwapOut.
@@ -708,6 +722,14 @@ 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 to prevent |this| to be killed when swapping out
+  // RenderViewHosts. This allows the unload handler to be run into background.
+  bool should_be_preserved_on_swap_out_;
+
+  // Set to true to have the renderer perform additional clean up if it had the
+  // unload handler run into the background previously.
+  bool need_to_perform_clean_up_on_swapped_out_;
+
   // Set to true when waiting for ViewHostMsg_SwapOut_ACK has timed out.
   bool has_timed_out_on_unload_;