commit 945a9d395b7971cde18d5d7bc69184f3e6fefa8d
Author: fago <nuppla@zites.net>
Date:   Wed Jun 19 18:53:17 2013 +0200

    Keep email field working without email module.

diff --git a/core/lib/Drupal/Core/Entity/Field/Type/EmailItem.php b/core/lib/Drupal/Core/Entity/Field/Type/EmailItem.php
index 940a682..6d878ed 100644
--- a/core/lib/Drupal/Core/Entity/Field/Type/EmailItem.php
+++ b/core/lib/Drupal/Core/Entity/Field/Type/EmailItem.php
@@ -36,4 +36,11 @@ public function getPropertyDefinitions() {
     }
     return static::$propertyDefinitions;
   }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function isEmpty() {
+    return !isset($this->values['value']) || $this->values['value'] === '';
+  }
 }
diff --git a/core/modules/email/email.module b/core/modules/email/email.module
index 72758e3..2d24c39 100644
--- a/core/modules/email/email.module
+++ b/core/modules/email/email.module
@@ -43,13 +43,6 @@ function email_field_info_alter(&$info) {
 }
 
 /**
- * Implements hook_field_is_empty().
- */
-function email_field_is_empty($item, $field_type) {
-  return !isset($item['value']) || $item['value'] === '';
-}
-
-/**
  * Implements hook_field_formatter_info_alter().
  */
 function email_field_formatter_info_alter(&$info) {