function testCreateRow_DefaultValues() {
  var getSchema = function() {
    var tableBuilder = new lf.schema.TableBuilder('Table');
    tableBuilder.
        addColumn('integer', lf.Type.INTEGER).
        addColumn('number', lf.Type.NUMBER).
        addColumn('string', lf.Type.STRING).
        addColumn('boolean', lf.Type.BOOLEAN).
        addColumn('datetime', lf.Type.DATE_TIME).
        addColumn('arraybuffer', lf.Type.ARRAY_BUFFER).
        addColumn('object', lf.Type.OBJECT);
    return tableBuilder.getSchema();
  };

  var tableSchema = getSchema();
  var row = tableSchema.createRow();
  assertTrue(row instanceof lf.Row);

  var payload = row.payload();
  assertNull(payload['arraybuffer']);
  assertFalse(payload['boolean']);
  assertEquals(0, payload['datetime'].getTime());
  assertEquals(0, payload['integer']);
  assertEquals(0, payload['number']);
  assertNull(payload['object']);
  assertEquals('', payload['string']);
}
Tests that the generated createRow() function produces the correct default
values for each column, based on the column's type and whether the column is
nullable by default.