diff -u b/core/lib/Drupal/Core/Config/CreationHash.php b/core/lib/Drupal/Core/Config/CreationHash.php
--- b/core/lib/Drupal/Core/Config/CreationHash.php
+++ b/core/lib/Drupal/Core/Config/CreationHash.php
@@ -62,7 +62,10 @@
    * {@inheritdoc}
    */
   public function generate($id) {
-    return $this->getPrefix() . '__' . $id;
+    // We need to replace dots in the ids since the uuid is being used in field
+    // and table names. Without this \Drupal\field\Tests\FieldImportDeleteTest
+    // does not pass.
+    return $this->getPrefix() . '__' . str_replace('.', '__', $id);
   }
 
 }
diff -u b/core/lib/Drupal/Core/Config/Entity/ConfigStorageController.php b/core/lib/Drupal/Core/Config/Entity/ConfigStorageController.php
--- b/core/lib/Drupal/Core/Config/Entity/ConfigStorageController.php
+++ b/core/lib/Drupal/Core/Config/Entity/ConfigStorageController.php
@@ -332,12 +332,7 @@
     // whether a configuration entity with the same ID (if any) already exists.
     $entity->enforceIsNew();
 
-    // Assign a new UUID if there is none yet.
-    if (!isset($entity->{$this->uuidKey})) {
-      $entity->{$this->uuidKey} = $this->creationHash->generate($entity->id());
-    }
     $entity->postCreate($this);
-
     // Modules might need to add or change the data initially held by the new
     // entity object, for instance to fill-in default values.
     $this->invokeHook('create', $entity);
@@ -347,6 +342,11 @@
       $entity->{$this->statusKey} = TRUE;
     }
 
+    // Assign a new UUID if there is none yet.
+    if (!isset($entity->{$this->uuidKey})) {
+      $entity->{$this->uuidKey} = $this->creationHash->generate($entity->id());
+    }
+
     return $entity;
   }
 
diff -u b/core/modules/breakpoint/lib/Drupal/breakpoint/Entity/Breakpoint.php b/core/modules/breakpoint/lib/Drupal/breakpoint/Entity/Breakpoint.php
--- b/core/modules/breakpoint/lib/Drupal/breakpoint/Entity/Breakpoint.php
+++ b/core/modules/breakpoint/lib/Drupal/breakpoint/Entity/Breakpoint.php
@@ -122,16 +122,16 @@
   /**
    * {@inheritdoc}
    */
-  public static function preCreate(EntityStorageControllerInterface $storage_controller, array &$values) {
+  public function postCreate(EntityStorageControllerInterface $storage_controller) {
     // Build an id if none is set. Since a particular name can be used by
     // multiple theme/modules we need to make a unique id.
-    if (empty($values['id'])) {
-      $values['id'] = $values['sourceType'] . '.' . $values['source'] . '.' . $values['name'];
+    if (empty($this->id)) {
+      $this->id = $this->sourceType . '.' . $this->source . '.' . $this->name;
     }
 
     // Set the label if none is set.
-    if (empty($values['label'])) {
-      $values['label'] = $values['name'];
+    if (empty($this->label)) {
+      $this->label = $this->name;
     }
   }
 
diff -u b/core/modules/breakpoint/lib/Drupal/breakpoint/Entity/BreakpointGroup.php b/core/modules/breakpoint/lib/Drupal/breakpoint/Entity/BreakpointGroup.php
--- b/core/modules/breakpoint/lib/Drupal/breakpoint/Entity/BreakpointGroup.php
+++ b/core/modules/breakpoint/lib/Drupal/breakpoint/Entity/BreakpointGroup.php
@@ -104,9 +104,9 @@
   /**
    * {@inheritdoc}
    */
-  public static function preCreate(EntityStorageControllerInterface $storage_controller, array &$values) {
-    if (empty($values['id'])) {
-      $values['id'] = $values['sourceType'] . '.' . $values['source'] . '.' . $values['name'];
+  public function postCreate(EntityStorageControllerInterface $storage_controller) {
+    if (empty($this->id)) {
+      $this->id = $this->sourceType . '.' . $this->source . '.' . $this->name;
     }
   }
 
diff -u b/core/modules/config/lib/Drupal/config/Tests/ConfigInstallWebTest.php b/core/modules/config/lib/Drupal/config/Tests/ConfigInstallWebTest.php
--- b/core/modules/config/lib/Drupal/config/Tests/ConfigInstallWebTest.php
+++ b/core/modules/config/lib/Drupal/config/Tests/ConfigInstallWebTest.php
@@ -98,7 +98,7 @@
     drupal_flush_all_caches();
     $default_config_entity = entity_load('config_test', 'dotted.default');
     $default_config_entity_creation_hash = $default_config_entity->uuid();
-    $this->assertEqual($default_config_entity_creation_hash, 'ModuleHandler::install__dotted.default');
+    $this->assertEqual($default_config_entity_creation_hash, 'ModuleHandler::install__dotted__default');
 
     $edit = array(
       'id' => 'test_creation_hash',
@@ -107,7 +107,7 @@
     $this->drupalPostForm('admin/structure/config_test/add', $edit, 'Save');
     $custom_config_entity = entity_load('config_test', 'test_creation_hash');
     $custom_config_entity_creation_hash = $custom_config_entity->uuid();
-    $this->assertFalse(strpos($custom_config_entity_creation_hash, 'ModuleHandler::install'), "Runtime generated configuration creation hash does not contain ModuleHandler::install");
+    $this->assertIdentical(FALSE, strpos($custom_config_entity_creation_hash, 'ModuleHandler::install'), "Runtime generated configuration creation hash does not contain ModuleHandler::install");
 
     \Drupal::moduleHandler()->uninstall(array('config_test'));
 
diff -u b/core/tests/Drupal/Tests/Core/Config/CreationHashTest.php b/core/tests/Drupal/Tests/Core/Config/CreationHashTest.php
--- b/core/tests/Drupal/Tests/Core/Config/CreationHashTest.php
+++ b/core/tests/Drupal/Tests/Core/Config/CreationHashTest.php
@@ -27,7 +27,7 @@
             ->will($this->returnValue('generated-uuid'));
 
     $creationHash = new CreationHash($uuid);
-    $this->assertEquals('generated-uuid__test.id', $creationHash->generate('test.id'));
+    $this->assertEquals('generated-uuid__test__id', $creationHash->generate('test.id'));
   }
 
   public function testCreationHashPrefix() {
@@ -38,12 +38,12 @@
 
     $creationHash = new CreationHash($uuid);
     $creationHash->setPrefix('CreationHashTest');
-    $this->assertEquals('CreationHashTest__test.id', $creationHash->generate('test.id'));
+    $this->assertEquals('CreationHashTest__test__id', $creationHash->generate('test.id'));
 
     // Ensure that the prefix cannot be reset. This allows themes to be enabled
     // by profiles in their hook_install implementation.
     $creationHash->setPrefix('AnotherPrefix');
-    $this->assertEquals('CreationHashTest__test.id', $creationHash->generate('test.id'));
+    $this->assertEquals('CreationHashTest__test__id', $creationHash->generate('test.id'));
   }
 
 }
only in patch2:
unchanged:
--- a/core/modules/breakpoint/lib/Drupal/breakpoint/Tests/BreakpointAPITest.php
+++ b/core/modules/breakpoint/lib/Drupal/breakpoint/Tests/BreakpointAPITest.php
@@ -31,7 +31,7 @@ public static function getInfo() {
   public function testConfigName() {
     // Try an invalid sourceType.
     $breakpoint = entity_create('breakpoint', array(
-      'label' => drupal_strtolower($this->randomName()),
+      'name' => drupal_strtolower($this->randomName()),
       'source' => 'custom_module',
       'sourceType' => 'oops',
     ));
@@ -74,8 +74,9 @@ public function testConfigName() {
     $this->assertTrue($exception, 'breakpoint_config_name: An exception is thrown when an invalid name is entered.');
 
     // Try a valid breakpoint.
-    $breakpoint->id = '';
-    $breakpoint->name = drupal_strtolower($this->randomName());
+    $breakpoint = entity_create('breakpoint', array(
+      'name' => drupal_strtolower($this->randomName()),
+    ));
     $breakpoint->mediaQuery = 'all';
 
     $exception = FALSE;
@@ -83,9 +84,10 @@ public function testConfigName() {
       $breakpoint->save();
     }
     catch (\Exception $e) {
+      $this->fail($e->getMessage());
       $exception = TRUE;
     }
     $this->assertFalse($exception, 'breakpoint_config_name: No exception is thrown when a valid breakpoint is passed.');
-    $this->assertEqual($breakpoint->id(), Breakpoint::SOURCE_TYPE_USER_DEFINED . '.custom_module.' . $breakpoint->name, 'breakpoint_config_name: A id is set when a valid breakpoint is passed.');
+    $this->assertEqual($breakpoint->id(), Breakpoint::SOURCE_TYPE_USER_DEFINED . '.user.' . $breakpoint->name, 'breakpoint_config_name: A id is set when a valid breakpoint is passed.');
   }
 }
only in patch2:
unchanged:
--- a/core/modules/breakpoint/lib/Drupal/breakpoint/Tests/BreakpointCRUDTest.php
+++ b/core/modules/breakpoint/lib/Drupal/breakpoint/Tests/BreakpointCRUDTest.php
@@ -28,7 +28,7 @@ public static function getInfo() {
   public function testBreakpointCRUD() {
     // Add a breakpoint with minimum data only.
     $breakpoint = entity_create('breakpoint', array(
-      'label' => drupal_strtolower($this->randomName()),
+      'name' => drupal_strtolower($this->randomName()),
       'mediaQuery' => '(min-width: 600px)',
     ));
     $breakpoint->save();