* gomoripeti/kernel/controlling_proc_badarg_doc/PR-1208/OTP-14022:
  controlling_process can return {error, badarg}

* sverker/kernel-erts-dependency:
  kernel: Add lost dependency to erts-8.1

In OTP-19.1 (c70ca686fe269db6079a2ca1c7e09cdfc0cfa903)
erts_code_purger:finish_after_on_load/2 was added
and called by code_server.erl.

For gen_tcp, gen_udp and gen_sctp controlling_process/2 can return
badarg if erlang:port_connect/2 fails with badarg. This can easily
happen if the new owner is not alive but in some race condition also
when the socket is closed right before port_connect/2 (and after the
previous socket function)
This commit documents this behaviour.

* raimo/diffserv-socket-option/OTP-13582:
  Tune 'tclass' semantics
  Implement IPV6_TCLASS

* bjorn/erts/on_load/ERL-240/OTP-13893:
  erts: Add nif_SUITE:t_on_load
  erts: Improve nif_SUITE:upgrade test
  Don't leak old code when loading a modules with an on_load function

Normally, calling code:delete/1 before re-loading the code for a
module is unnecessary but causes no problem.

But there will be be problems if the new code has an on_load function.
Code with an on_load function will always be loaded as old code
to allowed it to be easily purged if the on_load function would fail.
If the on_load function succeeds, the old and current code will be
swapped.

So in the scenario where code:delete/1 has been called explicitly,
there is old code but no current code. Loading code with an
on_load function will cause the reference to the old code to be
overwritten. That will at best cause a memory leak, and at worst
an emulator crash (especially if NIFs are involved).

To avoid that situation, we will put the code with the on_load
function in a special, third slot in Module.

ERL-240