CCrmActivityRestProxy::externalizeFields

protected function externalizeFields(&$fields, &$fieldsInfo)
{
	$storageTypeID = isset($fields['STORAGE_TYPE_ID'])
		? (int)$fields['STORAGE_TYPE_ID'] : CCrmActivity::GetDefaultStorageTypeID();

	if(isset($fields['STORAGE_ELEMENT_IDS']))
	{
		CCrmActivity::PrepareStorageElementIDs($fields);
		if($storageTypeID === Bitrix\Crm\Integration\StorageType::Disk)
		{
			$fields['FILES'] = $fields['STORAGE_ELEMENT_IDS'];
		}
		elseif($storageTypeID === Bitrix\Crm\Integration\StorageType::WebDav)
		{
			$fields['WEBDAV_ELEMENTS'] = $fields['STORAGE_ELEMENT_IDS'];
		}
		unset($fields['STORAGE_ELEMENT_IDS']);
	}
	parent::externalizeFields($fields, $fieldsInfo);
}