Throw exception if id not passed into discard

[eileenmcnaughton]

Overview

https://lab.civicrm.org/dev/drupal/-/issues/123 - may not be related but this seems a good precaution

Before

Calling BAO_Group::discard with NULL looks like it might over-delete.

After

Calling BAO_Group::discard with NULL would throw an exception

Technical Details

I can't find any evidence this is happening but it seems like a sensible precaution

Comments

[civibot]

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