[Freeciv-Dev] (PR#4259) ground_unit_transporter_capacity check fails

["Mike Kaufman" <kaufman@xxxxxxxxxxxxxxxxxxxxxx>]

with this script and CVS:

set xsize 60
set ysize 60
set randseed 962    
set seed 7704      
set gen 2
set landmass 35
set saveturns 40
set timeout -1    
set aifill 20    
hard            
create Caesar  
set endyear 2000
start

For introductory help, type 'help'.
> 
Game saved as civgame-2000.sav.gz
> 
Game saved as civgame-0500.sav.gz
> 
Game saved as civgame+0400.sav.gz
> civserver: sanitycheck.c:244: check_units: Assertion
> `ground_unit_transporter_capacity(x, y, pplayer) >= 0' failed.
Aborted (core dumped)

-mike