bug#1168: 23.0.60; facemenu-add-face-function and TeX-mode

[martin rudalics]

The following problem was initially described by Kostas Oikonomou on
help-gnu-emacs.  To reproduce open an arbitrary buffer in TeX mode and
turn off font-lock-mode.  Now select

  Edit->Text Properties->Background Color->Other

and at the prompt type

  yellow RET

Emacs responds with

  (error "Face ((:background yellow)) not configured for LaTeX mode")

IIUC `facemenu-add-face-function' in TeX-mode was configured for
transforming text like

  I want this bold.

into

  {\bf I want this bold.}

via marking and selecting the appropriate entry from the menu.  But by
default font-lock is active so this menu entry is dimmed and _not_
availabe.  When font-lock is deactivated this menu entry is available
but so are the Foreground and Background Color entries which are not
configured for TeX-mode and give raise to the error message above.

martin