[solved]r2387- Change to public stop tool cause crash

[z9999]

After changing a stop to public with public tool, simutrans crashed.
100% reproduced.

How to reprodece:
1. Load attached savegame.
2. As a player, build a stop on a bridge on the south side of stop A.
(This will be public because there is a stop on the ground road.)
3. As a player, build a stop on a bridge on the north side of stop A.
(This is a player's stop.)
4. Use public stop tool on that stop and change to public.
5. Click fast forward.

Result:
Crash.

[prissi]

I cannot built a stop on the south side: Not an allowed place for a stop error ... and also the other action does not create an error for me.

[z9999]

I cannot built a stop on the south side:

Did you press Ctrl key ?
That needs to reproduce crashing.
I reproduced this with release version of 102.0.

Solved in r2389. Thank you.