Update Superbalist\Flysystem\GoogleStorage\GoogleStorageAdapter to support VISIBILITY_NOT_SET

GoogleStorageAdapter.php

<?php

namespace app\adaptors;

use Google\Cloud\Storage\Acl;
use League\Flysystem\AdapterInterface;

/**
 * @package app\adaptors\GoogleStorageAdapter
 * Updated by Michael Kubler @kublermdk to support VISIBILITY_NOT_SET
 *
 * We rework the Superbalist\Flysystem\GoogleStorage\GoogleStorageAdapter
 * So that it can support NOT setting the Access Control Lists
 * This allows it to be used on Google Storage buckets with Access Control set to Unified
 *
 * If you attempt to upload a file to Google Storage with a bucket set to Unified Access Control then you get an error:
 *
 *    > Cannot insert legacy ACL for an object when uniform bucket-level access is enabled. Read more at https://cloud.google.com/storage/docs/uniform-bucket-level-access
 *
 * This allows you to set the visibility config to VISIBILITY_NOT_SET and it won't set the ACLs and will allow you to upload
 * @license Where applicable the license extends the existing Superbalist\Flysystem\GoogleStorage\GoogleStorageAdapter license or uses http://opensource.org/licenses/BSD-3-Clause
 *
 */
class GoogleStorageAdapter extends \Superbalist\Flysystem\GoogleStorage\GoogleStorageAdapter
{

    /**
     * @const  VISIBILITY_NOT_SET  ACLs not set
     */
    const VISIBILITY_NOT_SET = 'not-set';

    /**
     * {@inheritdoc}
     */
    public function setVisibility($path, $visibility)
    {
        $object = $this->getObject($path);

        if (in_array($visibility, [AdapterInterface::VISIBILITY_PRIVATE, self::VISIBILITY_NOT_SET])) {
            $object->acl()->delete('allUsers');
        } elseif ($visibility === AdapterInterface::VISIBILITY_PUBLIC) {
            $object->acl()->add('allUsers', Acl::ROLE_READER);
        }

        $normalised = $this->normaliseObject($object);
        $normalised['visibility'] = $visibility;

        return $normalised;
    }

    /**
     * @param string $visibility
     *
     * @return string
     */
    protected function getPredefinedAclForVisibility($visibility)
    {
        // -- Allow for NOT having the Access Control List set, which is required when you have the uniform bucket-level access enabled
        if ($visibility === self::VISIBILITY_NOT_SET) {
            return null;
        }
        return $visibility === AdapterInterface::VISIBILITY_PUBLIC ? 'publicRead' : 'projectPrivate';
    }
}