IrisGrid throws error if given table with no columns

[bmingles]

Description

IrisGrid throws a .js error if given a table with no columns.

This is the underlying cause of
https://deephaven.atlassian.net/browse/DH-14436

Steps to reproduce
Create a table with no columns

from deephaven import empty_table
x = empty_table(10)

Expected results
Table panel should load without error but show no columns or rows

Actual results

Versions

Engine Version: 0.22.0
Web UI Version: 0.31.1
Java Version: 17.0.6
Barrage Version: 0.5.0