[O] Bug: Mode line face is not updated when clock overruns [9.1.7 (release_9.1.7-466-ga16590.dirty @ /home/luke/elisp/org-mode/lisp/)]

[Luke]

The face of the clocked time does not seem to change when the clock 
overruns (typically it changes to a red background).

I'm no lisp expert, but after digging around in the code it looks like 
the problem is in org-clock-get-clock-string():

    662 (defun org-clock-get-clock-string ()
    663   "Form a clock-string, that will be shown in the mode line.
    664 If an effort estimate was defined for the current item, use
    665 01:30/01:50 format (clocked/estimated).
    666 If not, show simply the clocked time like 01:50."
    667   (let ((clocked-time (org-clock-get-clocked-time)))
    668     (propertize
    669      (if org-clock-effort

    ...

    683      'face 'org-mode-line-clock)))

It seems like the call to propertize (on line #668) is overwriting the 
face ('org-mode-line-clock-overrun) of the resulting string with 
'org-mode-line-clock. I think this change was introduced in commit 
6655429b8d.


Emacs  : GNU Emacs 24.5.1 (x86_64-pc-linux-gnu, GTK+ Version 3.18.9)
 of 2017-09-21 on lcy01-07, modified by Debian
Package: Org mode version 9.1.7 (release_9.1.7-466-ga16590.dirty @ 
/home/luke/elisp/org-mode/lisp/)