bug#4221: improve font-lock-comment-face on dark background low color terminals

[Dan Nicolaescu]

The patch below uses the high contrast "yellow" color for
font-lock-comment-face on low color terminals using a dark background
color.
Yellow is not used by many other font-lock faces on such terminals.

This will enable us to eliminate the need for the
font-lock-comment-delimiter-face. (which the patch does not do, it just
makes it identical to font-lock-comment-face, it will be done in an
incremental patch).


Index: lisp/font-lock.el
===================================================================
RCS file: /cvsroot/emacs/emacs/lisp/font-lock.el,v
retrieving revision 1.351
diff -u -3 -p -r1.351 font-lock.el
--- lisp/font-lock.el 2 Aug 2009 14:20:10 -0000 1.351
+++ lisp/font-lock.el 19 Aug 2009 05:15:42 -0000
@@ -1853,19 +1853,13 @@ Sets various variables using `font-lock-
     (((class color) (min-colors 8) (background light))
      (:foreground "red"))
     (((class color) (min-colors 8) (background dark))
-     )
+     (:foreground "yellow"))
     (t (:weight bold :slant italic)))
   "Font Lock mode face used to highlight comments."
   :group 'font-lock-faces)
 
 (defface font-lock-comment-delimiter-face
-  '((default :inherit font-lock-comment-face)
-    (((class grayscale)))
-    (((class color) (min-colors 16)))
-    (((class color) (min-colors 8) (background light))
-     :foreground "red")
-    (((class color) (min-colors 8) (background dark))
-     :foreground "red1"))
+  '((default :inherit font-lock-comment-face))
   "Font Lock mode face used to highlight comment delimiters."
   :group 'font-lock-faces)