[Contracts] add TranslatableInterface

Author: nicolas-grekas

TranslatableInterface.php

@@ -0,0 +1,20 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Contracts\Translation;
+
+/**
+ * @author Nicolas Grekas <p@tchwork.com>
+ */
+interface TranslatableInterface
+{
+    public function trans(TranslatorInterface $translator, string $locale = null): string;
+}

composer.json

@@ -27,7 +27,7 @@
     "minimum-stability": "dev",
     "extra": {
         "branch-alias": {
-            "dev-master": "2.2-dev"
+            "dev-master": "2.3-dev"
         },
         "thanks": {
             "name": "symfony/contracts",