bug#23272: 25.0.92; syntax-propertize-via-font-lock considered harmful

[Dmitry Gutov]

It makes it impossible to call syntax-propertize without enabling
font-lock-mode first, e.g. when delay-mode-hooks is used.

Example:

(with-temp-buffer
  (insert "-- -*- mode: ada -*-")
  (delay-mode-hooks
    (set-auto-mode))
  (syntax-propertize (point)))

=> (error "Font-lock trying to use keywords before setting them up")

I've hit this when working on a patch in
http://debbugs.gnu.org/cgi/bugreport.cgi?bug=23223#38.