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

[Glenn Morris]

Adam Christensen wrote:

>     (custom-theme-set-faces
>      'foo
>      '(region ((t (:background "LightSkyBlue1"))))
>      '(isearch ((t (:inherit region)))))
[...]
> This doesn't appear to change the background of isearch.

http://debbugs.gnu.org/cgi/bugreport.cgi?bug=8454#11

    "...:inherit only tells Emacs to consult the parent face if a face
    attribute is unspecified. If the attribute is specified, it
    overrides the inheritance. So if your Custom theme want to "cancel
    out", say, any existing foreground attribute setting, you need
    something like

    '(froob ((t (:foreground unspecified :inherit parent-face))))
    "