bug#14754: 24.3.50; `C-h v' needs to fill wide `pp' lines (493 chars wide?!)

[Drew Adams]

Sorry, but the patch I sent is no good.  Filling something that was
pretty-printed destroys pretty-printing (duh).

The problem remains.  It is that `pp' prints a flat list using a very
large width, which is inappropriate for buffer *Help* etc.

One solution might be to have a variable controlling the max width
(when possible) for pretty-printing, much as we have vars to control the
print-length etc.

> The lines in the *Help* buffer should respect `fill-column' as much as
> possible, other things being equal.
> emacs -Q
> C-h v imagemagick-enabled-types
> 
> You see the value printed on a single line that is 493 chars wide!
> That's ridiculous, and it does not play well with code that fits the
> *Help* frame or window to its buffer text etc.