[WIP] towards #6610 sudo workflow resolution

[kalefranz]

resolve #6610

Needs rebased following merge of #7180.

[kalefranz]

In addition to the first commit, also need to look at doing a better job with

    @property
    def envs_dirs(self):
        if self.root_writable:
            fixed_dirs = (
                join(self.root_prefix, 'envs'),
                join(self._user_data_dir, 'envs'),
                join('~', '.conda', 'envs'),
            )
        else:
            fixed_dirs = (
                join(self._user_data_dir, 'envs'),
                join(self.root_prefix, 'envs'),
                join('~', '.conda', 'envs'),
            )
        return tuple(IndexedSet(expand(p) for p in concatv(self._envs_dirs, fixed_dirs)))

    @property
    def pkgs_dirs(self):
        if self._pkgs_dirs:
            return tuple(IndexedSet(expand(p) for p in self._pkgs_dirs))
        else:
            cache_dir_name = 'pkgs32' if context.force_32bit else 'pkgs'
            return tuple(IndexedSet(expand(join(p, cache_dir_name)) for p in (
                self.root_prefix,
                self._user_data_dir,
            )))

[beeankha]

This pull request is being closed in order to reduce the number of outdated/stale PRs on this repo; if this work is still actively in progress, please feel free to re-open!