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

code from pantheon

* code from pantheon

wp/wp-content/plugins/wordpress-seo/src/conditionals/third-party/wpml-wpseo-conditional.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace Yoast\WP\SEO\Conditionals\Third_Party;
+
+use Yoast\WP\SEO\Conditionals\Conditional;
+
+/**
+ * Conditional that is met when the Yoast SEO Multilingual plugin,
+ * a glue plugin developed by and for WPML, is active.
+ */
+class WPML_WPSEO_Conditional implements Conditional {
+
+	/**
+	 * Path to the Yoast SEO Multilingual plugin file.
+	 *
+	 * @internal
+	 */
+	const PATH_TO_WPML_WPSEO_PLUGIN_FILE = 'wp-seo-multilingual/plugin.php';
+
+	/**
+	 * Returns whether or not the Yoast SEO Multilingual plugin is active.
+	 *
+	 * @return bool Whether or not the Yoast SEO Multilingual plugin is active.
+	 */
+	public function is_met() {
+		return \is_plugin_active( self::PATH_TO_WPML_WPSEO_PLUGIN_FILE );
+	}
+}