(svn r17684) -Fix: tcache.first_engine and rcache.first_engine need to be set before first callback/sprite-resolving. For RV fronts it was missing at all, causing livery selection to fail.

src/train_cmd.cpp

@@ -720,6 +720,7 @@ static CommandCost CmdBuildRailWagon(EngineID engine, TileIndex tile, DoCommandF
 		v->spritenum = rvi->image_index;
 
 		v->engine_type = engine;
+		v->tcache.first_engine = INVALID_ENGINE; // needs to be set before first callback
 
 		DiagDirection dir = GetRailDepotDirection(tile);
 
@@ -900,6 +901,7 @@ CommandCost CmdBuildRailVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1,
 //		v->dest_tile = 0;
 
 		v->engine_type = p1;
+		v->tcache.first_engine = INVALID_ENGINE; // needs to be set before first callback
 
 		v->reliability = e->reliability;
 		v->reliability_spd_dec = e->reliability_spd_dec;