(internal-facep): Length is now 10.

(internal-facep): Length is now 10.
(make-face, x-create-frame-with-faces): Make a face 10 elements long.
(internal-set-face-1): Don't call set-face-attribute-internal
if NAME is nil.
(set-face-font): Set the auto-flag to t or nil.
(face-spec-set): Clear out the font at the start,
if it was set automatically before.
(face-font-explicit): New function.
(set-face-font-auto): New function.
(set-face-font-explicit): New function.
(copy-face): Copy the face-font-external flag.
(internal-try-face-font): Use set-face-font-auto.