bug#20141: 24.4.91; Helm is broken after last changes in eieio

[Stefan Monnier]

>                     (mapcar #'car (get 'yas--template 'cl-struct-slots)))

Right, this is linked to the cl-preloaded.el change rather than to the
eieio change.

cl-structs now come with a proper class object (itself a struct),
whereas they used to store their run-time description using a set of
symbol properties (such as cl-struct-slots).

I'll have to document this change, indeed.
And for backward compatibility's sake, it looks like we're going to
have to provide the old symbol properties.


        Stefan