bug#10850: 23.4; Error in post-command-hook: (args-out-of-range tooltip-show 17 12)

[Leo]

1. eval:
(icomplete-mode 1)
(setq completion-cycle-threshold 5)

2. C-h f and type in tooltip-show

3. type TAB for 1 or 2 times

Error in post-command-hook: (args-out-of-range tooltip-show 17 12)

The error is caused by passing a FROM arg greater than the STRING length
to substring in icomplete-completions.

Leo