bug#57691: 29.0.50; image-tests failures

[Stefan Kangas]

Eli Zaretskii <eliz@gnu.org> writes:

> So I guess the test assumes something non-portable?  If I invoke the
> test with --eval "(setq w32-use-native-image-API nil)", the
> image-tests-image-metadata/gif test passes.
>
>> I'm not sure if it matters or not, but do you happen to know which
>> version of giflib you're using?
>
> If w32-use-native-image-API is nil, my Emacs uses libgif v5.1.0.  By
> default, libgif is not used at all; instead, Emacs uses MS-Windows
> native APIs in the system library gdiplus.dll to display GIF images.

Ah, I forgot about the native image stuff.

It seems to me that the test currently assumes that we do NOT use a
native image API.

I don't know if we (1) need to adjust the delay on MS-Windows along the
lines of what we do in image.c [see commit 3de2462da7], or (2) should
change the test to set w32-use-native-image-API to nil, or (3) if we
should just skip the test on MS-Windows.

If we would like to change this like in (1) above, I guess the place to
do so is w32image.c:448.  Perhaps similarly for nsimage.m:546.
I couldn't find anything related to Qdelay in haikuimage.c, but maybe
there too.