bug#10630: 24.0.92; :inheirt isn't being inherited in custom themes

[Chong Yidong]

Adam Christensen <pope@shifteleven.com> writes:

>     (deftheme foo
>       "A test theme.")
>     
>     (custom-theme-set-faces
>      'foo
>      '(region ((t (:background "LightSkyBlue1"))))
>      '(isearch ((t (:inherit region)))))
>     
>     (provide-theme 'foo)
>
> This doesn't appear to change the background of isearch. This did work
> in Emacs 23.3.

I've committed a change to trunk which fixes this, by making theme faces
completely replace defface specs.