Remove svn_auth_cleanup_walk()?

While reviewing new-to-1.8 APIs, I found myself rather confused by
svn_auth_cleanup_walk(). It took me a bit to understand the approach, and
ultimately I realize that this was because the function and its plumbing
seemed to conflate the idea of the "simple" auth credential type with our
on-disk, plaintext-most-of-the-time cache. Anyway, I now feel like I have a
pretty good idea what the function does and claims to do ... which gives me
grounds to make some complaints. :-)

IMO, the function should allow cleanup even when no-auth-cache is set in the
auth parameter hash, but doesn't. I think that's because (as far as I can
tell) Bert (who wrote the function) thought that flag meant "pretend like
there is no auth cache", when it instead means merely "don't cache new auth
creds". That's trivially fixable. (My justification is that it's probably
precisely those folks who've since set no-auth-cache that might want to go
back and purge data Subversion has previously cached.)

Also, if I'm reading it correctly, it will allow orphaned information to
remain in third-party keyring providers while still blowing away the
metadata which gives that information its context within Subversion. We use
our plaintext disk cache to hold most of the information -- everything but
the most private bits -- even when a third-party provider (Gnome Keyring,
etc.) is in use. As far as I can tell, this function will consider creds
stored in this hybrid manner the same as it would those stored entirely in
the plaintext file, and won't inform the cleanup callback function about
this detail.

Personally, I'd like to remove this API before we ship 1.8 and rethink it in
light of the work that I plan to revisit post-1.8 with the master passphrase
feature. I'm certainly willing to do that (or some other more incrementally
improving) work. But I'm not keen on simply jettisoning someone else's
code, so I'm seeking feedback here.

Thoughts?

-- 
C. Michael Pilato <cmpilato_at_collab.net>
CollabNet   <>   www.collab.net   <>   Enterprise Cloud Development