task: #3589208 Always use the file contents to determine asset aggregate filename hashes

    ];

    foreach ($group['items'] as $key => $asset) {

      $normalized['asset_group']['items'][$key] = array_diff_key($asset, $group_keys, $omit_keys);

      // If the version is set to -1, this means there is no version in the

      // library definition. To ensure unique hashes when unversioned files

      // change, replace the version with a hash of the file contents.

      if ($asset['version'] === -1) {

        $normalized['asset_group']['items'][$key]['version'] = hash('xxh64', file_get_contents($asset['data']));

      }

      // Drupal core adds a version to libraries even when they don't change.

      // Conversely some themes or modules may fail to update the version when

      // files do change. Therefore always replace the version with a hash of

      // the file contents so that it always, but only, updates when the file

      // itself changes. Check for file existence here because missing files

      // should be dealt with elsewhere than when generating the hash.

      $normalized['asset_group']['items'][$key]['version'] = file_exists($asset['data']) ? hash_file('xxh64', $asset['data']) : $asset['version'];

    }

    // The asset array ensures that a valid hash can only be generated via the

    // same code base. Additionally use the hash salt to ensure that hashes are