dev/core#795 Fix PHP warning when updating a multiselect country field.

[mlutfy]

Overview

https://lab.civicrm.org/dev/core/issues/795

Steps to reproduce:

• Create a new custom field for Contacts of type Country - Multiselect.
• Run the following test script:

<?php

\Drupal::service('civicrm')->initialize();

error_reporting(E_ALL);
$result = civicrm_api3( 'Contact', 'create', [
  'id' => 131,
  'custom_33' => [1039, 1041],
]);

Resulting warning:

explode() expects parameter 2 to be string, array given CustomValueTable.php:127

Before

warning

After

no warning

Technical Details

Seems like a pretty obvious error in the code. Mostly harmless, but warnings are annoying. According to the git blame, it's been like that forever (pre-2013).

The warning was not visible when using the API explorer or when updating a contact record through the normal CiviCRM interface.

[civibot]

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[yashodha]

looks good, can be merged.

[mlutfy]

Thanks @yashodha - I've taken the liberty to add 'merge-on-pass'