CRM-21447: Relationship Report: move variable handling to beginPostProcessCommon

[mlutfy]

Overview

For 99.99% of users, this should not have an impact. However, for people accessing the report from the APIv3, this fixes using a report instance where the report filters on a relationship_type_id. It also fixes a bug when exporting report data with the Export to Excel extension.

Before

fatal error Unknown column '11_b_a' in 'where clause'

After

no fatal error 🌈

Technical Details

I moved a hack from the postProcess() to beginCommonPostProcess().

Comments

You can test from the API Explorer:

• Create a report instance of contact/relationship that has a filter on "relationship Type" = ""
• Take note of the instance_id
• Go to the API Explorer (civicrm/api/explorer), and run: ReportTemplate.getrows with variable: instance_id=1234 (where 1234 is your instance_id noted above).

[eileenmcnaughton]

This is totally consistent with the purpose of introducing the beginPostProcessCommon function. I feel confident enough about this to merge based on a read of the code