(svn r4572) Remove vehicle_leave_tile_proc
There's exactly one implemented function (unbarring a level crossing) and one place where it can be triggered (a train leaves a level crossing)
It's a bit overkill, so just handle this one case where it can happen

/* $Id$ */

#ifndef NEWGRF_SPRITEGROUP_H
#define NEWGRF_SPRITEGROUP_H

SpriteGroup *AllocateSpriteGroup(void);
void InitializeSpriteGroupPool(void);

#endif /* NEWGRF_SPRITEGROUP_H */