bug#26918: 25.2; rmail edit corrupts mail if content-type header not displayed

[Ken Olum]

   From: Glenn Morris <rgm@gnu.org>
   Date: Mon, 05 Jun 2017 17:16:56 -0400

   It seems neither rmail user has an opinion. ;)

That bad, is it?

   What do you suggest?

I'd be in favor of looking first at the edited message, and if there is
no Content-Type header there, looking at the full headers of the
original message.  If Content-Type is ignored, but the user adds one in
the edit buffer, I would replace the original one in the message with the
new one supplied by the user.  I think this is the general way that
added headers are handled.

                                        Ken