Resolve #3365254 "Moksu error fix"

Closes #3365254

moksu.theme

@@ -34,7 +34,7 @@ function moksu_page_alter(&$page)
 function moksu_preprocess_page(&$variables)
 {
 	$theme = \Drupal::theme()->getActiveTheme()->getName();
-	$variables['theme_path'] = drupal_get_path('theme', $theme);
+	$variables['theme_path'] = \Drupal::service('extension.list.theme')->getPath($theme);
 	$variables['base_path'] = base_path();
 	$variables['front_page'] = Url::fromRoute('<front>');
 }
@@ -45,7 +45,9 @@ function moksu_preprocess_page_title(&$variables)
 		$variables['title_prefix'] = array('#markup' => '<div class="tt_article_title_hidden">');
 		$variables['title_suffix'] = array('#markup' => '</div>');
 	}
-	$variables['node_id'] = $node->id();
+	if($node instanceof \Drupal\node\NodeInterface) {
+		$variables['node_id'] = $node->id();
+	}
 }
 function moksu_form_alter(&$form, &$form_state, $form_id)
 {