Way back when I added support for core boot classic installs, we did not
have a way to indicate whether the installed model preferred to be
installed encrypted or unencrypted. Roll time on 9 months or so and our
API now supports a list of capabilites and we can define that we can
indicate which is preferred by putting it first in the list.
One part of the implementation is a bit delicate really -- relying on
list.sort() being stable -- so maybe we should clean that up. But I
think the other changes make everything nicer.
35e66a4805