We've had trouble with eclean and equery vanishing in our SDKs from time
to time. Although I don't know the root cause it seemed to be some
confusion in the ebuild environment, perhaps a mis-match between the
eclasses, profiles, and ebuilds. Updating all of those seemed to resolve
the issue and to make sure other environments are ok force a re-install
of portage and gentoolkit to clean things up.
The old chroot version system we inherited from Chromium OS always
assumes that a newly unpacked tarball is the latest and greatest but
since we version the SDK in the same way as target builds we can use
that version for these sorts of upgrade scripts and not make assumptions
about how late and great the starting tarball was.
The first upgrade script simply aborts to force the user to recreate
their chroot when moving from python 2.6 to 2.7.
