diff --git a/core/modules/block/lib/Drupal/block/BlockRenderController.php b/core/modules/block/lib/Drupal/block/BlockRenderController.php
index 82134c6..4ecb2a1 100644
--- a/core/modules/block/lib/Drupal/block/BlockRenderController.php
+++ b/core/modules/block/lib/Drupal/block/BlockRenderController.php
@@ -82,18 +82,17 @@ public function view(EntityInterface $entity, $view_mode = 'full', $langcode = N
   public function viewMultiple(array $entities = array(), $view_mode = 'full', $langcode = NULL) {
     $build = array();
     foreach ($entities as $entity_id => $entity) {
-      $block = $entity->getPlugin()->blockBuild();
+      $build[$entity_id] = $entity->getPlugin()->blockBuild();
       // Allow blocks to be empty, do not add in the defaults.
-      if (!empty($block)) {
-        $block = $this->getBuildDefaults($entity, $view_mode, $langcode) + $block;
+      if (!empty($build[$entity_id])) {
+        $build[$entity_id] = $this->getBuildDefaults($entity, $view_mode, $langcode) + $build[$entity_id];
       }
 
       // All blocks, even when empty, should be available for altering.
       $id = str_replace(':', '__', $entity->get('plugin'));
       list(, $name) = $entity->id();
-      drupal_alter(array('block_view', "block_view_$id", "block_view_$name"), $block, $entity);
+      drupal_alter(array('block_view', "block_view_$id", "block_view_$name"), $build[$entity_id], $entity);
 
-      $build[$entity_id] = $block;
     }
     return $build;
   }
diff --git a/core/modules/block/lib/Drupal/block/BlockStorageController.php b/core/modules/block/lib/Drupal/block/BlockStorageController.php
index 02374ff..6fb5ec5 100644
--- a/core/modules/block/lib/Drupal/block/BlockStorageController.php
+++ b/core/modules/block/lib/Drupal/block/BlockStorageController.php
@@ -51,7 +51,7 @@ public function loadByProperties(array $values = array()) {
     $blocks = $this->load();
     foreach ($values as $key => $value) {
       $blocks = array_filter($blocks, function($block) use ($key, $value) {
-        return $value == $block->get($key);
+        return $value === $block->get($key);
       });
     }
     return $blocks;
diff --git a/core/modules/block/lib/Drupal/block/Plugin/Core/Entity/Block.php b/core/modules/block/lib/Drupal/block/Plugin/Core/Entity/Block.php
index 7f27640..e8ccc63 100644
--- a/core/modules/block/lib/Drupal/block/Plugin/Core/Entity/Block.php
+++ b/core/modules/block/lib/Drupal/block/Plugin/Core/Entity/Block.php
@@ -107,7 +107,7 @@ class Block extends ConfigEntityBase {
   protected $theme;
 
   /**
-   * The module owning this block.
+   * The module owning this plugin.
    *
    * @var string
    */
diff --git a/core/modules/block/lib/Drupal/block/Plugin/Type/BlockManager.php b/core/modules/block/lib/Drupal/block/Plugin/Type/BlockManager.php
index b7186b0..181d32c 100644
--- a/core/modules/block/lib/Drupal/block/Plugin/Type/BlockManager.php
+++ b/core/modules/block/lib/Drupal/block/Plugin/Type/BlockManager.php
@@ -12,7 +12,6 @@
 use Drupal\Core\Plugin\Discovery\AlterDecorator;
 use Drupal\Core\Plugin\Discovery\CacheDecorator;
 use Drupal\Component\Plugin\Factory\DefaultFactory;
-use Drupal\Core\Plugin\Mapper\ConfigMapper;
 
 /**
  * Manages discovery and instantiation of block plugins.
@@ -32,7 +31,6 @@ public function __construct() {
     $this->discovery = new AlterDecorator($this->discovery, 'block');
     $this->discovery = new CacheDecorator($this->discovery, 'block_plugins:' . language(LANGUAGE_TYPE_INTERFACE)->langcode, 'cache_block');
     $this->factory = new DefaultFactory($this);
-    $this->mapper = new ConfigMapper($this);
   }
 
 }