rebase from live enviornment

wp/plugins/wordpress-seo/admin/notifiers/interface-notification-handler.php

@@ -0,0 +1,21 @@
+<?php
+/**
+ * WPSEO plugin file.
+ *
+ * @package WPSEO\Admin\Notifiers
+ */
+
+/**
+ * Dictates the required methods for a Notification Handler implementation.
+ */
+interface WPSEO_Notification_Handler {
+
+	/**
+	 * Handles the notification object.
+	 *
+	 * @param Yoast_Notification_Center $notification_center The notification center object.
+	 *
+	 * @return void
+	 */
+	public function handle( Yoast_Notification_Center $notification_center );
+}