Fix 02e770ff: allow estimating CloneVehicle if short on money (#8748)

CheckCompanyHasMoney() was also executed when not using DC_EXEC,
resulting in an error about shortage of money instead of the
estimation.
This mostly is a problem for AI players, as they will have no
way to know how much it would have cost.

src/script/api/ai_changelog.hpp

@@ -21,6 +21,9 @@
  * \li AICargo::GetName
  * \li AIPriorityQueue
  *
+ * Other changes:
+ * \li AIVehicle::CloneVehicle now correctly returns estimate when short on cash
+ *
  * \b 1.10.0
  *
  * API additions:

src/vehicle_cmd.cpp

@@ -987,16 +987,14 @@ CommandCost CmdCloneVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint
 
 		/* Now clone the vehicle's name, if it has one. */
 		if (!v_front->name.empty()) CloneVehicleName(v_front, w_front);
-	}
 
-	/* Since we can't estimate the cost of cloning a vehicle accurately we must
-	 * check whether the company has enough money manually. */
-	if (!CheckCompanyHasMoney(total_cost)) {
-		if (flags & DC_EXEC) {
+		/* Since we can't estimate the cost of cloning a vehicle accurately we must
+		 * check whether the company has enough money manually. */
+		if (!CheckCompanyHasMoney(total_cost)) {
 			/* The vehicle has already been bought, so now it must be sold again. */
 			DoCommand(w_front->tile, w_front->index | 1 << 20, 0, flags, GetCmdSellVeh(w_front));
+			return total_cost;
 		}
-		return total_cost;
 	}
 
 	return total_cost;