When their local master pipe endpoint is closed, associated interface endpoints are notified synchronously of a connection error.

This is problematic because it's extremely subtle. As with bug 854993, it can easily lead to an error handler being invoked while its bound object is partially destructed. The only way to prevent this would be to explicitly close the associated bindings before closing the master binding.

Because this is so subtle, and because the behavior as-is does not seem to be necessary for any practical reasons, we should fix change it: if a master endpoint is closed, its local associated endpoints can receive a connection error asynchronously (or not at all of course, if they happen to be destroyed before their async handler can run).
 

When their local master pipe endpoint is closed, associated interface endpoints are notified synchronously of a connection error.

This is problematic because it's extremely subtle. As with bug 854993, it can easily lead to an error handler being invoked while its bound object is partially destructed. The only way to prevent this would be to explicitly close the associated bindings before closing the master binding.

Because this is so subtle, and because the behavior as-is does not seem to be necessary for any practical reasons, we should change it: if a master endpoint is closed, its local associated endpoints can receive a connection error asynchronously (or not at all of course, if they happen to be destroyed before their async handler can run).