updated version for 2019 ;)

legacy/class-helper.php

 <?php
 
-if ( ! defined( 'ABSPATH' ) ) {
-	exit;
-} // Exit if accessed directly
+if ( ! defined( 'ABSPATH' ) ) exit; // Exit if accessed directly
 
 if ( ! class_exists( 'WPDesk_Helper_Plugin' ) ) {
 
 	class WPDesk_Helper_Plugin {
 
-	    /** @var array */
 		protected $plugin_data;
 
-		/** @var string */
 		protected $text_domain;
 
-		/** @var string  */
 		protected $ame_activated_key;
 
-		/** @var string  */
 		protected $ame_activation_tab_key;
 
-		/**
-		 * @param array $plugin_data
-		 */
 		function __construct( $plugin_data ) {
 			global $wpdesk_helper_plugins;
 
 			$this->plugin_data = $plugin_data;
-			if ( ! isset( $wpdesk_helper_plugins ) ) {
-				$wpdesk_helper_plugins = array();
-			}
+			if ( ! isset( $wpdesk_helper_plugins ) ) $wpdesk_helper_plugins = array();
 			$plugin_data['helper_plugin'] = $this;
 			$wpdesk_helper_plugins[] = $plugin_data;
 
@@ -38,38 +27,28 @@ if ( ! class_exists( 'WPDesk_Helper_Plugin' ) ) {
 
 		}
 
-		/**
-		 * @return void
-		 */
 		public function inactive_notice() { ?>
-			<?php if ( ! current_user_can( 'manage_options' ) ) {
-				return;
-			} ?>
-			<?php if ( 1 == 1 && isset( $_GET['page'] ) && $this->ame_activation_tab_key == $_GET['page'] ) {
-				return;
-			} ?>
+			<?php if ( ! current_user_can( 'manage_options' ) ) return; ?>
+			<?php if ( 1==1 && isset( $_GET['page'] ) && $this->ame_activation_tab_key == $_GET['page'] ) return; ?>
             <div class="update-nag">
 				<?php printf( __( 'The %s%s%s License Key has not been activated, so the plugin is inactive! %sClick here%s to activate the license key and the plugin.', 'wpdesk-plugin' ), '<strong>', $this->plugin_data['product_id'], '</strong>', '<a href="' . esc_url( admin_url( 'admin.php?page='.$this->ame_activation_tab_key ) ) . '">', '</a>' ); ?>
             </div>
 			<?php
 		}
 
-		/**
-		 * @param bool $add_notice
-		 *
-		 * @return bool
-		 */
+
 		function is_active( $add_notice = false ) {
 			if ( get_option( $this->ame_activated_key, '0' ) != 'Activated' ) {
 				if ( $add_notice ) {
 					add_action( 'admin_notices', array( $this, 'inactive_notice' ) );
 				}
-
 				return false;
-			} else {
+			}
+			else {
 				return true;
 			}
 		}
 
 	}
+
 }