dev/core#932 Fix dedupe contacts flip selection

[mlutfy]

Overview

How to reproduce on dmaster:

• Go to: Contacts > Find and merge duplicates
• Select the "Name and address" rule, which brings you here: https://dmaster.demo.civicrm.org/civicrm/contact/dedupefind?reset=1&action=update&rgid=7#

Then notice that)

• when we click on "flip" for a single entry, it seems to flip, but the "merge" link is the same, so doing the actual merge does not flip the direction.
• if we click the checkbox for the result, then click the "Flip selected duplicates", nothing happens.

Before

Flipping had no visual effect, and multi-flipping had no effect at all (did not update the dupes in the prevnext cache).

After

Works as expected.

Technical Details

I had to partially revert a change that was done a long time ago regarding $prevNextId = $_REQUEST['pnid'];. Is there a way to use CRM_Utils_Request::retrieveValue on an URL param that can sometimes be an array? (it would be better to have two different AJAX endpoints for this, imho)

https://lab.civicrm.org/dev/core/issues/932

[civibot]

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[eileenmcnaughton]

I gave this a quick test & agree this fixes the bug & does not introduce a security issue. Mergint