[Form] Fixed invalid use of FormException

src/Symfony/Component/Form/ButtonBuilder.php

@@ -13,6 +13,7 @@ namespace Symfony\Component\Form;
 
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
 use Symfony\Component\Form\Exception\FormException;
+use Symfony\Component\Form\Exception\InvalidArgumentException;
 
 /**
  * A builder for {@link Button} instances.
@@ -62,7 +63,7 @@ class ButtonBuilder implements \IteratorAggregate, FormBuilderInterface
     public function __construct($name, array $options)
     {
         if (empty($name) && 0 != $name) {
-            throw new FormException('Buttons cannot have empty names.');
+            throw new InvalidArgumentException('Buttons cannot have empty names.');
         }
 
         $this->name = (string) $name;

src/Symfony/Component/Form/Exception/InvalidArgumentException.php

@@ -0,0 +1,21 @@
+<?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\Component\Form\Exception;
+
+/**
+ * Base InvalidArgumentException for the Form component.
+ *
+ * @author Bernhard Schussek <bschussek@gmail.com>
+ */
+class InvalidArgumentException extends \InvalidArgumentException implements ExceptionInterface
+{
+}