Used to be that emacs --reverse-video would open Emacs with black
background. Now it opens with white background as though the flag
wasn't specified. I Git bisected the Savannah repo to:

15e14b165dcbc6566a0459b0d5e66f89080f569e is the first bad commit
commit 15e14b165dcbc6566a0459b0d5e66f89080f569e
Author: Chong Yidong <cyd@gnu.org>
Date:   Sat Dec 21 23:31:09 2013 +0800

    Don't make faces when loading Custom themes.
   
    * custom.el (custom-theme-recalc-face): Do nothing if the face is
    undefined.  Thus, theme settings for undefined faces do not take
    effect until the faces are defined with defface, the same as with
    theme variables.
   
    * faces.el (face-spec-set): Use face-spec-recalc in all cases.
    (face-spec-reset-face): Don't assign extra properties in temacs.
    (face-spec-recalc): Apply X resources too.