Fix #8462: Don't check whether to grow a town road on water (#8471)

src/town_cmd.cpp

@@ -932,8 +932,8 @@ static bool IsRoadAllowedHere(Town *t, TileIndex tile, DiagDirection dir)
 		 * If that fails clear the land, and if that fails exit.
 		 * This is to make sure that we can build a road here later. */
 		RoadType rt = GetTownRoadType(t);
-		if (DoCommand(tile, ((dir == DIAGDIR_NW || dir == DIAGDIR_SE) ? ROAD_Y : ROAD_X) | (rt << 4), 0, DC_AUTO, CMD_BUILD_ROAD).Failed() &&
-				DoCommand(tile, 0, 0, DC_AUTO, CMD_LANDSCAPE_CLEAR).Failed()) {
+		if (DoCommand(tile, ((dir == DIAGDIR_NW || dir == DIAGDIR_SE) ? ROAD_Y : ROAD_X) | (rt << 4), 0, DC_AUTO | DC_NO_WATER, CMD_BUILD_ROAD).Failed() &&
+				DoCommand(tile, 0, 0, DC_AUTO | DC_NO_WATER, CMD_LANDSCAPE_CLEAR).Failed()) {
 			return false;
 		}
 	}