Reintroduce the 2.2 name mangling code, until we get are more flexible solution.

Reintroduce the 2.2 name mangling code, until we get are more flexible solution.

Even for a hash/cache setup, this code needs some more work, in particular
it needs to use mangle_get_prefix() etc and to move to unicode internals.

Andrew Bartlett
(This used to be commit ad8aa470575c39fcbc7f1440bf1081d7ea31c0aa)