GridLongList list = asList(1,2,3,4,5,6);
assertEquals(2, list.removeValue(0, 3));
assertEquals(asList(1,2,4,5,6), list);
assertEquals(-1, list.removeValue(1, 1));
assertEquals(-1, list.removeValue(0, 3));
assertEquals(4, list.removeValue(0, 6));
assertEquals(asList(1,2,4,5), list);