bug#50642: 27.2; autoload xref-pulse-momentarily

[Howard Melman]

I'm not sure about this but can xref-pulse-momentarily be
autoloaded?

I'm using consult and it has a consult-after-jump-hook which
recommends xref-pulse-momentarily as something you may want
to use in it. I set it and xref-after-jump-hook to:
'(reposition-window xref-pulse-momentarily).

It works great, but if I use consult before xref I get the error:
run-hooks: Symbol's function definition is void: xref-pulse-momentarily
If I add an autoload call myself it does not error.

I looked but didn't find a more suitable function to use.
It seems like pulse.el should define a function suitable for
use in a hook, but in its absense xref-pulse-momentarily
does seem like the best option (though I couldn't follow its
implementation). 


In GNU Emacs 27.2 (build 1, x86_64-apple-darwin18.7.0, Carbon Version 158 
AppKit 1671.6)
of 2021-03-27 built on Traviss-Mac.local

-- 

Howard