Fix PHP 7 strict warnings CRM_Core_DAO::getContactIDsFromComponent passed by reference

[andrewpthompson]

Overview

This PR fixes PHP 7 strict warnings on several search task forms, i.e. creating a PDF letter after searching for Memberships or Event participants.

Before

PHP notices are displayed when the search task forms are displayed for Memberships, Event participants on PHP7+.

After

No PHP notices are displayed for those forms.

Technical Details

The e-notices were caused by this obsolete pattern; the & can be safely removed:

    $this->_contactIds = &CRM_Core_DAO::getContactIDsFromComponent($this->_memberIds,
      'civicrm_membership'
    );

It is present in

CRM/Event/Form/Task.php
CRM/Grant/Form/Task.php
CRM/Pledge/Form/Task.php
CRM/Core/Form/Task.php

and had already been resolved in:

CRM/Case/Form/Task.php
CRM/Contribute/Form/Task.php

Comments

For Pledges, Grants and Core, although the same obsolete pattern was present it does not appear to be used. I have changed these in line with Membership and Event and tested.

[civibot]

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[mattwire]

This is a PHP4 hangover. I've reviewed the code and confirm it is ok to merge.

[mattwire]

ok to merge @eileenmcnaughton @seamuslee001