Apply php-cs-fixer fix --rules nullable_type_declaration_for_default_null_value

Author: nicolas-grekas

TranslatableInterface.php

@@ -16,5 +16,5 @@
  */
 interface TranslatableInterface
 {
-    public function trans(TranslatorInterface $translator, string $locale = null): string;
+    public function trans(TranslatorInterface $translator, ?string $locale = null): string;
 }

TranslatorInterface.php

@@ -63,5 +63,5 @@ interface TranslatorInterface
      *
      * @throws \InvalidArgumentException If the locale contains invalid characters
      */
-    public function trans(string $id, array $parameters = [], string $domain = null, string $locale = null);
+    public function trans(string $id, array $parameters = [], ?string $domain = null, ?string $locale = null);
 }

TranslatorTrait.php

@@ -43,7 +43,7 @@ public function getLocale()
     /**
      * {@inheritdoc}
      */
-    public function trans(?string $id, array $parameters = [], string $domain = null, string $locale = null): string
+    public function trans(?string $id, array $parameters = [], ?string $domain = null, ?string $locale = null): string
     {
         if (null === $id || '' === $id) {
             return '';