bug#29198: Cursor fringe arrow indicator not updating.

[Keith David Bershatsky]

Yes, "M-x" triggers an immediate removal of the old indicator and places the 
new indicator at the current line position.

I would recommend adding an exception to the redisplay optimization to check 
for a change of placement to the built-in overlay fringe arrow indicator.  
Since the fringe arrow indicator has been an existing feature of Emacs for 
quite some time (built-in to xdisp.c), it should (in my opinion) work out of 
the box without the need for the user to force a redisplay with additional Lisp 
code.

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DATE:  [11-07-2017 12:37:43] <07 Nov 2017 22:37:43 +0200>
FROM:  Eli Zaretskii <eliz@gnu.org>
> 
> * * *
> 
> Does it update if you type "M-x"?  If it does, you aren't triggering a
> thorough enough redisplay.