Add check for table 'from' field inside ImageColumn

[lvismer]

Let's say you have an image field on your table. The current solution for ImageColumn will not query the image column from the database because somehow the existing label callback returns null which in turn results in $this->field being null.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.