bug#39972: 28.0.50; which-function no longer returning current Java method in Emacs 27

[Eli Zaretskii]

> Date: Thu, 21 May 2020 17:42:11 +0000
> Cc: Philipp Stephani <p.stephani2@gmail.com>, 39972@debbugs.gnu.org
> From: Alan Mackenzie <acm@muc.de>
> 
> > Is it possible to come up with something simpler for emacs-27?
> 
> I think the change (in master) to CC Mode's value of
> add-log-current-defun could be put into emacs-27 on its own.  This should
> be safe.
> 
> The patch which made this change (bug #39972) was:
> 5989432d15feb4439e759d2c0e28233ca22a7604
> "CC Mode: Fix bug #39972, by fixing c-display-defun-name for nested
> defuns"
> Date:   Wed May 20 19:02:26 2020 +0000.
> 
> What do you say to putting this into emacs-27?

If it fixes the problem reported in this bug report, it's fine by me
to cherry-pick it to emacs-27.

Thanks.