Issue #3040166 by oriol_e9g, Mile23, willzyx, Berdir, alexpott, catch,...

      $this->htmlOutputClassName = str_replace("\\", "_", get_called_class());

      $this->htmlOutputDirectory = DRUPAL_ROOT . '/sites/simpletest/browser_output';

      // Do not use the file_system service so this method can be called before

      // it is available.

      if (!is_dir($this->htmlOutputDirectory)) {

        mkdir($this->htmlOutputDirectory, 0775, TRUE);

      // it is available. Checks !is_dir() twice around mkdir() because a

      // concurrent test might have made the directory and caused mkdir() to

      // fail. In this case we can still use the directory even though we failed

      // to make it.

      if (!is_dir($this->htmlOutputDirectory) && !mkdir($this->htmlOutputDirectory, 0775, TRUE) && !is_dir($this->htmlOutputDirectory)) {

        throw new \RuntimeException(sprintf('Unable to create directory: %s', $this->htmlOutputDirectory));

      }

      if (!file_exists($this->htmlOutputDirectory . '/.htaccess')) {

        file_put_contents($this->htmlOutputDirectory . '/.htaccess', "<IfModule mod_expires.c>\nExpiresActive Off\n</IfModule>\n");