Merged in feature/from-pantheon (pull request #16)

code from pantheon

* code from pantheon

wp/wp-content/plugins/wordpress-seo-premium/src/initializers/plugin.php

@@ -0,0 +1,68 @@
+<?php
+
+namespace Yoast\WP\SEO\Premium\Initializers;
+
+use WPSEO_Capability_Manager_Factory;
+use WPSEO_Premium;
+use WPSEO_Premium_Register_Capabilities;
+use Yoast\WP\SEO\Conditionals\No_Conditionals;
+use Yoast\WP\SEO\Helpers\Options_Helper;
+use Yoast\WP\SEO\Initializers\Initializer_Interface;
+
+/**
+ * Class Plugin.
+ */
+class Plugin implements Initializer_Interface {
+
+	use No_Conditionals;
+
+	/**
+	 * The options helper.
+	 *
+	 * @var Options_Helper
+	 */
+	protected $options_helper;
+
+	/**
+	 * Plugin constructor.
+	 *
+	 * @param Options_Helper $options_helper The options helper.
+	 */
+	public function __construct( Options_Helper $options_helper ) {
+		$this->options_helper = $options_helper;
+	}
+
+	/**
+	 * Loads the redirect handler.
+	 *
+	 * @return void
+	 */
+	public function initialize() {
+		\add_action( 'plugins_loaded', [ $this, 'load' ], 15 );
+
+		$wpseo_premium_capabilities = new WPSEO_Premium_Register_Capabilities();
+		$wpseo_premium_capabilities->register_hooks();
+
+		\register_deactivation_hook( \WPSEO_PREMIUM_FILE, [ $this, 'wpseo_premium_deactivate' ] );
+	}
+
+	/**
+	 * The premium setup
+	 */
+	public function load() {
+		new WPSEO_Premium();
+	}
+
+	/**
+	 * Cleans up Premium on deactivation.
+	 *
+	 * @return void
+	 */
+	public function wpseo_premium_deactivate() {
+		\do_action( 'wpseo_register_capabilities_premium' );
+		WPSEO_Capability_Manager_Factory::get( 'premium' )->remove();
+		if ( $this->options_helper->get( 'toggled_tracking' ) !== true ) {
+			$this->options_helper->set( 'tracking', false );
+		}
+	}
+}