Translator component has default domain for null implemented no need to have default translation domain logic in 3 different places

Author: Tobion

Extension/Core/Type/BaseType.php

@@ -56,7 +56,7 @@ public function buildView(FormView $view, FormInterface $form, array $options)
                 $uniqueBlockPrefix = '_'.$blockName;
             }
 
-            if (!$translationDomain) {
+            if (null === $translationDomain) {
                 $translationDomain = $view->parent->vars['translation_domain'];
             }
         } else {
@@ -76,10 +76,6 @@ public function buildView(FormView $view, FormInterface $form, array $options)
         }
         $blockPrefixes[] = $uniqueBlockPrefix;
 
-        if (!$translationDomain) {
-            $translationDomain = 'messages';
-        }
-
         $view->vars = array_replace($view->vars, array(
             'form' => $view,
             'id' => $id,

Tests/Extension/Core/Type/BaseTypeTest.php

@@ -112,7 +112,7 @@ public function testDefaultTranslationDomain()
             ->getForm()
             ->createView();
 
-        $this->assertEquals('messages', $view['child']->vars['translation_domain']);
+        $this->assertNull($view['child']->vars['translation_domain']);
     }
 
     public function testPassLabelToView()