A KIO daemon

[David Faure]

After the discussion on https://gerrit.vesnicky.cesnet.cz/r/#/c/323/, I just 
had another idea (inspired by a discussion with Alex Fiestas (iirc) long 
ago)...

We could combine the 4 kded modules installed by KIO into a single daemon, say 
"kiod".

These modules are:
kssld + kcookiejar + kpasswdserver + proxyscout.
and the favicon module, which should really move in there too, from libkonq, 
since KIO has a runtime dependency on it.

"kiod" would still use KDEDModule as the base class for modules to load, i.e. 
it would be a lightweight kded (without the ksycoca stuff, the dependency on 
kdeinit, or even the legacy KService dependency).

And since all these modules provide services on request (rather than being 
things that have to run all the time, like some kded modules that are doing 
some watching), there's no need to explicitly start kiod during the boot 
sequence, it just gets autostarted via DBus whenever the first call to it is 
being made.

This solves issues like "I need a cookie, this starts kded, which itself has a 
long list of modules to load on startup". kiod would not do that, modules 
would all get loaded on-demand (the first ssl-enabled slave loads kssld, the 
first http slave loads cookiejar, the first slave requesting a password loads 
kpasswdserver, etc.)

It seems to me like a good intermediate solution between "everything depends 
on kded" and "everyone of the 28 kded modules becomes a standalone daemon".
KIO would have its own daemon, grouping 5 or more of these modules, and that
keeps things modular, resolving a bit of the kded<->kio inter-dependency (*) 
(at least for KIOCore... I still need a replacement for ksycoca before the 
same can be said about KIOWidgets).

(*) not a real compile-time inter-dependency, but rather the fact that the KIO 
unittests have to work without kded since kded is a runtime dependency of KIO, 
which depends on kio at compile-time (indirectly).

-- 
David Faure, faure at kde.org, http://www.davidfaure.fr
Working on KDE Frameworks 5