The default method implementations cause problems when trying to
override them with different types in a direct call class.
For the `Recv__delete__` case there's a simple solution: omit it if
there are any arguments, because it doesn't make much sense to specify
arguments and then completely ignore them, and the no-arg case isn't a
problem for overriding.
Differential Revision: https://phabricator.services.mozilla.com/D62977
--HG--
extra : moz-landing-system : lando