Comment 5 for bug 1324100

I was reminded about destroy notifies recently when I had to do some glib hacking.

Although their primary purpose is to provide a kind of destructor for things that might be freed in the background and/or have no guarantee of a callback being made at all (and so might be freed in the background). A secondary purpose is to be a consistent destructor that you can't forget to call.

I don't think Mir has the same strong use case per the primary purpose in glib, but it would be somewhat harmless functionality to add. The only cost is adding yet more functions to the client API and/or client ABI breaks :(