I thought that `hexrgb.el' and `color-lab.el' were going to be merged.
I suggested the name `color.el' for the combination, which was accepted.
See the thread, from 2010/11:
http://lists.gnu.org/archive/html/emacs-devel/2010-11/msg00897.html
http://lists.gnu.org/archive/html/emacs-devel/2010-11/msg00894.html

Instead, it seems that all that has happened so far is that `color-lab.el' was
renamed `color.el'.  AFAICT there is nothing from `hexrgb.el' in the file.  In
addition, Yidong mentioned moving `read-color' there, but that has not been done
yet either.

I've merged the two libraries now, moved `read-color' to it, and cleaned things
up (e.g. doc).  When there was overlap I kept the best version (e.g. most
precise or most general).  I did not include anything from `eyedropper.el' (e.g.
for `read-color').

Attached is the result, both a patch from the latest `color.el' and the new
result.  (`read-color' also needs to be removed from `faces.el' - I did not
include that patch.)