bug#41897: 28.0.50; JavaScript comment filling with mhtml-mode

[Tom Tromey]

>>>>> "Alan" == Alan Mackenzie <acm@muc.de> writes:

Alan> (ii) An enhancement to CC Mode, used by mhtml-mode and js-mode, which
Alan> invalidates a CC Mode cache used by the filling code.  This gets rid of
Alan> a few strange looking bugs;

I wonder if js-mode can be changed not to use cc-mode like this.
Looking at js.el, it seems like this is the origin of a use of advice
in-core, which is generally frowned upon:

    ;; FIXME: Such redefinitions are bad style.  We should try and use some 
other
    ;; way to get the same result.
    (defun js--fill-c-advice (js-fun)
    ...

Tom