only in patch2:
unchanged:
--- a/core/lib/Drupal/Core/Config/Context/ConfigContext.php
+++ b/core/lib/Drupal/Core/Config/Context/ConfigContext.php
@@ -12,6 +12,7 @@
 use Drupal\Component\Utility\NestedArray;
 use Drupal\Component\Uuid\UuidInterface;
 use Symfony\Component\EventDispatcher\EventDispatcher;
+use Symfony\Component\EventDispatcher\EventDispatcherInterface;
 
 /**
  * Defines the base configuration context object.
@@ -64,7 +65,7 @@ class ConfigContext implements ContextInterface {
    * @param \Drupal\Component\Uuid\UuidInterface
    *   The UUID service.
    */
-  public function __construct(EventDispatcher $event_dispatcher, UuidInterface $uuid) {
+  public function __construct(EventDispatcherInterface $event_dispatcher, UuidInterface $uuid) {
     $this->eventDispatcher = $event_dispatcher;
     $this->uuidService = $uuid;
   }
only in patch2:
unchanged:
--- /dev/null
+++ b/core/tests/Drupal/Tests/Core/Config/ConfigImporterTest.php
@@ -0,0 +1,193 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Tests\Core\Config\ConfigImporterTest.
+ */
+
+namespace Drupal\Tests\Core\Config {
+
+use Drupal\Core\Config\ConfigImporter;
+use Drupal\Tests\UnitTestCase;
+
+/**
+ * Tests the config importer.
+ *
+ * @see \Drupal\Core\Config\ConfigImporter
+ */
+class ConfigImporterTest extends UnitTestCase {
+
+  /**
+   * The actual tested config importer.
+   *
+   * @var \Drupal\Core\Config\ConfigImporter
+   */
+  protected $configImporter;
+
+  /**
+   * The config comparer for the actual storage.
+   *
+   * @var \Drupal\Core\Config\StorageComparerInterface|PHPUnit_Framework_MockObject_MockObject
+   */
+  protected $storageComparer;
+
+  /**
+   * The config comparer for the local storage.
+   *
+   * @var \Drupal\Core\Config\StorageComparerInterface|PHPUnit_Framework_MockObject_MockObject
+   */
+  protected $localComparer;
+
+  /**
+   * The mocked config factory.
+   *
+   * @var \Drupal\Core\Config\ConfigFactory|PHPUnit_Framework_MockObject_MockObjecty
+   */
+  protected $configFactory;
+
+  /**
+   * The mocked entity manager.
+   *
+   * @var \Drupal\Core\Entity\EntityManager|PHPUnit_Framework_MockObject_MockObjecty
+   */
+  protected $entityManager;
+
+  /**
+   * The mocked lock backend.
+   *
+   * @var \Drupal\Core\Lock\LockBackendInterface|PHPUnit_Framework_MockObject_MockObjecty
+   */
+  protected $lock;
+
+  /**
+   * The mocked event dispatcher.
+   *
+   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface|PHPUnit_Framework_MockObject_MockObjecty
+   */
+  protected $dispatcher;
+
+  /**
+   * The mocked UUID service.
+   *
+   * @var \Drupal\Component\Uuid\UuidInterface|PHPUnit_Framework_MockObject_MockObjecty
+   */
+  protected $uuid;
+
+  public static function getInfo() {
+    return array(
+      'name' => 'Config importer',
+      'description' => 'Tests the config importer.',
+      'group' => 'Configuration'
+    );
+  }
+
+  protected function setUp() {
+    $this->storageComparer = $this->getMock('Drupal\Core\Config\StorageComparerInterface');
+    $this->storageComparer->expects($this->any())
+      ->method('getEmptyChangelist')
+      ->will($this->returnValue(array('create' => array(), 'delete' => array(), 'update' => array())));
+
+    $this->dispatcher = $this->getMock('Symfony\Component\EventDispatcher\EventDispatcherInterface');
+    $this->configFactory = $this->getMockBuilder('Drupal\Core\Config\ConfigFactory')
+      ->disableOriginalConstructor()
+      ->getMock();
+    $this->entityManager = $this->getMockBuilder('Drupal\Core\Entity\EntityManager')
+      ->disableOriginalConstructor()
+      ->getMock();
+    $this->lock = $this->getMock('Drupal\Core\Lock\LockBackendInterface');
+    $this->uuid = $this->getMock('Drupal\Component\Uuid\UuidInterface');
+    $this->localComparer = $this->getMock('Drupal\Core\Config\StorageComparerInterface');
+
+    $this->configImporter = new ConfigImporter($this->storageComparer, $this->dispatcher, $this->configFactory, $this->entityManager, $this->lock, $this->uuid, $this->localComparer);
+  }
+
+  /**
+   * Tests import with conflicts.
+   *
+   * @see \Drupal\Core\Config\ConfigImporter::checkForConflicts()
+   * @see \Drupal\Core\Config\ConfigImporter::import()
+   *
+   * @expectedException \Drupal\Core\Config\ConfigImporterException
+   */
+  public function testImportConflictCheckingWithConflicts() {
+    $this->storageComparer->expects($this->any())
+      ->method('getChangelist')
+      ->will($this->returnValue(array('test_entity.example_config_a', 'test_entity.example_config_b')));
+
+    $this->localComparer->expects($this->any())
+      ->method('getChangelist')
+      ->will($this->returnValue(array('test_entity.example_config_b', 'test_entity.example_config_c')));
+
+    $this->lock->expects($this->any())
+      ->method('acquire')
+      ->will($this->returnValue(TRUE));
+
+    $this->configImporter->import();
+  }
+
+  /**
+   * Tests import conflict checking without conflicts.
+   *
+   * @see \Drupal\Core\Config\ConfigImporter::checkForConflicts()
+   * @see \Drupal\Core\Config\ConfigImporter::import()
+   *
+   * @expectedException \Drupal\Core\Config\ConfigImporterException
+   */
+  public function testImportConflictCheckingWithOutConflicts() {
+    $this->storageComparer->expects($this->any())
+      ->method('getChangelist')
+      ->will($this->returnValue(array('test_entity.example_config_a', 'test_entity.example_config_b')));
+
+    $this->localComparer->expects($this->any())
+      ->method('getChangelist')
+      ->will($this->returnValue(array('test_entity.example_config_c', 'test_entity.example_config_d')));
+
+    $this->lock->expects($this->any())
+      ->method('acquire')
+      ->will($this->returnValue(TRUE));
+
+    $storage = $this->getMock('Drupal\Core\Config\StorageInterface');
+    $storage->expects($this->any())
+      ->method('read')
+      ->will($this->returnValue(array('key' => 'value')));
+
+    // @TODO this doesn't work yet.
+    $this->storageComparer->expects($this->any())
+      ->method('getTargetStorage')
+      ->will($this->returnValue($storage));
+
+    $this->dispatcher->expects($this->at(0))
+      ->method('dispatch')
+      ->with('config.importer.validate', $this->isInstanceOf('Drupal\Core\Config\ConfigImporterEvent'));
+
+    $this->dispatcher->expects($this->at(1))
+      ->method('dispatch')
+      ->with('config.importer.delete', $this->isInstanceOf('Drupal\Core\Config\ConfigImporterEvent'));
+
+    $this->dispatcher->expects($this->at(1))
+      ->method('dispatch')
+      ->with('config.importer.delete', $this->isInstanceOf('Drupal\Core\Config\ConfigImporterEvent'));
+
+    $this->dispatcher->expects($this->at(2))
+      ->method('dispatch')
+      ->with('config.importer.create', $this->isInstanceOf('Drupal\Core\Config\ConfigImporterEvent'));
+    $this->dispatcher->expects($this->at(3))
+      ->method('dispatch')
+      ->with('config.importer.update', $this->isInstanceOf('Drupal\Core\Config\ConfigImporterEvent'));
+
+    // @TODO this doesn't work yet.
+//    $this->configImporter->import();
+  }
+
+}
+
+}
+
+namespace {
+  if (!function_exists('config_get_entity_type_by_name')) {
+    function config_get_entity_type_by_name($name) {
+      list($entity_type) = explode('.', $name);
+      return $entity_type;
+    }
+  }
+}