2844457-->t() should be used instead of t() for Drupal 8 version

Closes #2844457

src/Form/VisualizationSettingsForm.php

@@ -45,9 +45,9 @@ class VisualizationSettingsForm extends ConfigFormBase {
     $config = $this->config('visualization.settings');
     $form['library'] = array(
       '#type' => 'select',
-      '#title' => t('Preferred charting library'),
+      '#title' => $this->t('Preferred charting library'),
       '#options' => $options,
-      '#description' => t('Your charting library of preference will be used when generating charts (as long as it offers support for the requested type). The available options are the charting libraries detected on your system, please refer to the help section for more information about enabling more libraries.'),
+      '#description' => $this->t('Your charting library of preference will be used when generating charts (as long as it offers support for the requested type). The available options are the charting libraries detected on your system, please refer to the help section for more information about enabling more libraries.'),
       '#default_value' => $config->get('library'),
     );