Unable to query with delta group

When using EFQ with a group membership field, a $delta_group cannot be passed into either fieldCondition() or fieldLanguageCondition(). This causes a MySQL error:

Unknown column 'ogm.delta' in 'where clause'

. This is because EFQ expects fields to have a delta column if a $delta_group is specified, but the og_membership table does not have a delta column. This would be solved by simply using a delta column in this table, but I wanted to bring the issue up before proposing a patch.