bug#21650: fix should be underneath MH-E

[Mike Kupfer]

Bill Wohler wrote:

> Katsumi Yamaoka <yamaoka@jpl.org> wrote:
> > My solution is below.  Tested briefly.  This patch moves the
> > binding of shr-inhibit-images and shr-blocked-images to Gnus
> > from mm.  So, MH-E has to do a similar thing.
> 
> I disagree. This only works for shr and defeats encapsulation.

I think what makes this a non-trivial problem is wanting more
flexibility than just a binary yes-no decision, which is what
mm-inline-text-html-with-images currently provides.  That's why
gnus-blocked-images is a regexp (or a function that returns a regexp).

Could mm-inline-text-html-with-images be generalized to be more like
gnus-blocked-images?  (For example, nil means don't retrieve anything, t
means retrieve everything, a string would be a regexp of what URLs will
be retrieved.)  Then shr could use mm-inline-text-html-with-images
instead of shr-blocked-images, and MH-E users would have a single knob
that could control any of the different rendering back-ends.

mike