Skip null value for latest, earliest function

[navis]

testQuery(
    "WITH X AS ("
    + " SELECT * FROM "
    + " (VALUES"
    + "   (0, 'A', 1, null, null),"
    + "   (0, 'B', null, 2, null),"
    + "   (0, 'C', null, null, 3),"
    + "   (1, 'A', 4, null, null),"
    + "   (1, 'B', null, 5, null),"
    + "   (1, 'C', null, null, 6)"
    + " ) AS T (__time, asset, p1, p2, p3)"
    + ")"
    + " SELECT LATEST(p1), LATEST(p2), EARLIEST(p3) FROM X",
    new Object[]{4, 5, 3}
);