Handle smart groups created in previous Civis which include relation_permission

[highfalutin]

Overview

Fixes https://lab.civicrm.org/dev/core/issues/390: Smart groups created before 5.5.0 using "relation_permission" break on upgrade to 5.5.0

Before

• In Civi 5.4, create a smart group based on a relationship search.
• Upgrade to 5.5, clear cache and try to open the group.
• Error: DB Error: syntax error

After

• In Civi 5.4, create a smart group based on a relationship search.
• Upgrade to 5.5, clear cache and try to open the group.
• Group opens as expected.

Technical Details

When you create a Smart Group for a relationship search, the form values which are saved include relation_permission. Prior to 5.5.0, the operator was "=" and the value was scalar. As of 5.5.0, the operator is "IN" and the value is an array.

[eileenmcnaughton]

I'm OK merging this since it gives us the immediate fix - but I'd prefer to see either form conversion or using a function that transforms various formats (I can do an example later on) - but I think this is fine for now

[totten]

jenkins, test this please

[totten]

Added merge on pass based on review from the 5.5 variant #12803.

[eileenmcnaughton]

test fails unrelated