PMA\libraries\File::getRawContent PHP Method

    public function getRawContent()
    {
        if (null === $this->_content) {
            if ($this->isUploaded() && !$this->checkUploadedFile()) {
                return false;
            }
            if (!$this->isReadable()) {
                return false;
            }
            if (function_exists('file_get_contents')) {
                $this->_content = file_get_contents($this->getName());
            } elseif ($size = filesize($this->getName())) {
                $handle = fopen($this->getName(), 'rb');
                $this->_content = fread($handle, $size);
                fclose($handle);
            }
        }
        return $this->_content;
    }

     $response = PMA\libraries\Response::getInstance();
     $response->addJSON('prefs', json_encode($settings['config_data']));
     $response->addJSON('mtime', $settings['mtime']);
     exit;
 } else {
     if (isset($_POST['submit_import'])) {
         // load from JSON file
         $json = '';
         if (isset($_POST['import_type']) && $_POST['import_type'] == 'text_file' && isset($_FILES['import_file']) && $_FILES['import_file']['error'] == UPLOAD_ERR_OK && is_uploaded_file($_FILES['import_file']['tmp_name'])) {
             $import_handle = new File($_FILES['import_file']['tmp_name']);
             $import_handle->checkUploadedFile();
             if ($import_handle->isError()) {
                 $error = $import_handle->getError();
             } else {
                 // read JSON from uploaded file
                 $json = $import_handle->getRawContent();
             }
         } else {
             // read from POST value (json)
             $json = isset($_POST['json']) ? $_POST['json'] : null;
         }
         // hide header message
         $_SESSION['userprefs_autoload'] = true;
         $config = json_decode($json, true);
         $return_url = isset($_POST['return_url']) ? $_POST['return_url'] : null;
         if (!is_array($config)) {
             if (!isset($error)) {
                 $error = __('Could not import configuration');
             }
         } else {
             // sanitize input values: treat them as though