bug#18334: 24.3.93; ImageMagick: eww shows favicon animations in search results

[Glenn Morris <rgm@gnu.org>]

>> Should image-multi-frame-p, a new function in 24.4, stop using
>> image-default-frame-delay as a default value for DELAY? Or should each
>> caller of image-multi-frame-p temporarily let-bind
>> image-default-frame-delay to nil if it doesn't want to treat images
>> that are missing DELAY value as animations?
>
> I think I was intending it to work the first way, not the second way
> (which sounds a bit yucky?). But I don't seem to have implemented it
> right. No idea what I was thinking...

I think perhaps I meant to do something like the following, which I
applied to emacs-24.

However, AFAICS now nothing is animated in eww.
Perhaps this is related to shr's preference for ImageMagick and the fact
that that backend still does not return a delay
(http://debbugs.gnu.org/10747).

In theory ImageMagick should be used only when rescaling is needed, but
it seems to be used all (?) the time (because in shr-put-image, size is
often nil?).

--- a/lisp/image.el	2014-02-25 21:59:14 +0000
+++ b/lisp/image.el	2014-09-14 23:59:57 +0000
@@ -637,8 +637,8 @@
 	   (images (plist-get metadata 'count))
 	   (delay (plist-get metadata 'delay)))
       (when (and images (> images 1))
-	(if (or (not (numberp delay)) (< delay 0))
-	    (setq delay image-default-frame-delay))
+	(and delay (or (not (numberp delay)) (< delay 0))
+	     (setq delay image-default-frame-delay))
 	(cons images delay)))))