diff --git a/core/lib/Drupal/Core/Cache/StaticCache/StaticCache.php b/core/lib/Drupal/Core/Cache/StaticCache/StaticCache.php
index 1be728a..fa61227 100644
--- a/core/lib/Drupal/Core/Cache/StaticCache/StaticCache.php
+++ b/core/lib/Drupal/Core/Cache/StaticCache/StaticCache.php
@@ -3,7 +3,6 @@
 namespace Drupal\Core\Cache\StaticCache;
 
 use Drupal\Core\Cache\Cache;
-
 use Drupal\Core\Cache\MemoryBackend;
 
 /**
@@ -48,15 +47,15 @@ protected function prepareItem($cache, $allow_invalid) {
   /**
    * {@inheritdoc}
    */
-  public function set($cid, $data, $expire = Cache::PERMANENT, array $tags = array()) {
+  public function set($cid, $data, $expire = Cache::PERMANENT, array $tags = []) {
     assert('\Drupal\Component\Assertion\Inspector::assertAllStrings($tags)', 'Cache Tags must be strings.');
-    $this->cache[$cid] = (object) array(
+    $this->cache[$cid] = (object) [
       'cid' => $cid,
       'data' => $data,
       'created' => $this->getRequestTime(),
       'expire' => $expire,
       'tags' => $tags,
-    );
+    ];
   }
 
 }
diff --git a/core/lib/Drupal/Core/Cache/StaticCache/StaticCacheInterface.php b/core/lib/Drupal/Core/Cache/StaticCache/StaticCacheInterface.php
index 8c98194..a26ae96 100644
--- a/core/lib/Drupal/Core/Cache/StaticCache/StaticCacheInterface.php
+++ b/core/lib/Drupal/Core/Cache/StaticCache/StaticCacheInterface.php
@@ -4,7 +4,6 @@
 
 use Drupal\Core\Cache\CacheBackendInterface;
 use Drupal\Core\Cache\CacheTagsInvalidatorInterface;
-use Drupal\Core\Cache\StaticCache\StaticCacheInterface;
 
 /**
  * Defines an interface for static cache implementations.
diff --git a/core/lib/Drupal/Core/Config/Entity/ConfigEntityStorage.php b/core/lib/Drupal/Core/Config/Entity/ConfigEntityStorage.php
index ab04e25..399aafe 100644
--- a/core/lib/Drupal/Core/Config/Entity/ConfigEntityStorage.php
+++ b/core/lib/Drupal/Core/Config/Entity/ConfigEntityStorage.php
@@ -109,6 +109,7 @@ class ConfigEntityStorage extends EntityStorageBase implements ConfigEntityStora
    *   The static cache backend.
    */
   public function __construct(EntityTypeInterface $entity_type, ConfigFactoryInterface $config_factory, UuidInterface $uuid_service, LanguageManagerInterface $language_manager, StaticCacheInterface $static_cache = NULL) {
+    // @todo Remove this line in Drupal 9.0.x and make $static_cache required.
     $static_cache = isset($static_cache) ? $static_cache : \Drupal::service('entity.static_cache');
     parent::__construct($entity_type, $static_cache);
 
@@ -125,7 +126,8 @@ public static function createInstance(ContainerInterface $container, EntityTypeI
       $entity_type,
       $container->get('config.factory'),
       $container->get('uuid'),
-      $container->get('language_manager')
+      $container->get('language_manager'),
+      $container->get('entity.static_cache')
     );
   }
 
@@ -324,7 +326,7 @@ protected function has($id, EntityInterface $entity) {
    * {@inheritdoc}
    */
   protected function getCacheId($id) {
-    return parent::getCacheId($id) . ':' .  $config_overrides_key = $this->overrideFree ? '' : implode(':', $this->configFactory->getCacheKeys());
+    return parent::getCacheId($id) . ':' . $this->overrideFree ? '' : implode(':', $this->configFactory->getCacheKeys());
   }
 
   /**
diff --git a/core/lib/Drupal/Core/Entity/ContentEntityStorageBase.php b/core/lib/Drupal/Core/Entity/ContentEntityStorageBase.php
index 176a216..2d5cd6b 100644
--- a/core/lib/Drupal/Core/Entity/ContentEntityStorageBase.php
+++ b/core/lib/Drupal/Core/Entity/ContentEntityStorageBase.php
@@ -44,10 +44,11 @@
    *   The entity manager.
    * @param \Drupal\Core\Cache\CacheBackendInterface $cache
    *   The cache backend to be used.
-   * @param \Drupal\Core\Cache\CacheBackendInterface $static_cache
-   *   The cache backend to be used.
+   * @param \Drupal\Core\Cache\StaticCache\StaticCacheInterface $static_cache
+   *   The static cache backend.
    */
   public function __construct(EntityTypeInterface $entity_type, EntityManagerInterface $entity_manager, CacheBackendInterface $cache, StaticCacheInterface $static_cache = NULL) {
+    // @todo Remove this line in Drupal 9.0.x and make $static_cache required.
     $static_cache = isset($static_cache) ? $static_cache : \Drupal::service('entity.static_cache');
     parent::__construct($entity_type, $static_cache);
     $this->bundleKey = $this->entityType->getKey('bundle');
@@ -636,7 +637,7 @@ public function resetCache(array $ids = NULL) {
     if ($ids) {
       parent::resetCache($ids);
       if ($this->entityType->isPersistentlyCacheable()) {
-        $cids = array();
+        $cids = [];
         foreach ($ids as $id) {
           $cids[] = $this->buildCacheId($id);
         }
diff --git a/core/lib/Drupal/Core/Entity/EntityStorageBase.php b/core/lib/Drupal/Core/Entity/EntityStorageBase.php
index 4ef3c50..009fb8e 100644
--- a/core/lib/Drupal/Core/Entity/EntityStorageBase.php
+++ b/core/lib/Drupal/Core/Entity/EntityStorageBase.php
@@ -76,7 +76,7 @@
   /**
    * The static cache.
    *
-   * @var \Drupal\Core\StaticCache\StaticCacheInterface
+   * @var \Drupal\Core\Cache\StaticCache\StaticCacheInterface
    */
   protected $staticCache;
 
@@ -102,6 +102,7 @@ public function __construct(EntityTypeInterface $entity_type, StaticCacheInterfa
     $this->uuidKey = $this->entityType->getKey('uuid');
     $this->langcodeKey = $this->entityType->getKey('langcode');
     $this->entityClass = $this->entityType->getClass();
+    // @todo Remove this line in Drupal 9.0.x and make $static_cache required.
     $this->staticCache = isset($static_cache) ? $static_cache : \Drupal::service('entity.static_cache');
     $this->cacheTag = 'entity_static_cache:' . $this->entityTypeId;
   }
@@ -562,4 +563,5 @@ public function getAggregateQuery($conjunction = 'AND') {
    *   The name of the service for the query for this entity storage.
    */
   abstract protected function getQueryServiceName();
+
 }
diff --git a/core/lib/Drupal/Core/Entity/KeyValueStore/KeyValueEntityStorage.php b/core/lib/Drupal/Core/Entity/KeyValueStore/KeyValueEntityStorage.php
index 972a047..048052a 100644
--- a/core/lib/Drupal/Core/Entity/KeyValueStore/KeyValueEntityStorage.php
+++ b/core/lib/Drupal/Core/Entity/KeyValueStore/KeyValueEntityStorage.php
@@ -61,7 +61,7 @@ class KeyValueEntityStorage extends EntityStorageBase {
    *   The UUID service.
    * @param \Drupal\Core\Language\LanguageManagerInterface $language_manager
    *   The language manager.
-   * @param \Drupal\Core\StaticCache\StaticCacheInterface $static_cache
+   * @param \Drupal\Core\Cache\StaticCache\StaticCacheInterface $static_cache
    *   The static cache.
    */
   public function __construct(EntityTypeInterface $entity_type, KeyValueStoreInterface $key_value_store, UuidInterface $uuid_service, LanguageManagerInterface $language_manager, StaticCacheInterface $static_cache = NULL) {
@@ -82,7 +82,8 @@ public static function createInstance(ContainerInterface $container, EntityTypeI
       $entity_type,
       $container->get('keyvalue')->get('entity_storage__' . $entity_type->id()),
       $container->get('uuid'),
-      $container->get('language_manager')
+      $container->get('language_manager'),
+      $container->get('entity.static_cache')
     );
   }
 
diff --git a/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php b/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php
index a5d7245..f2c50b3 100644
--- a/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php
+++ b/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php
@@ -159,6 +159,7 @@ public function getFieldStorageDefinitions() {
    *   The static cache backend to be used.
    */
   public function __construct(EntityTypeInterface $entity_type, Connection $database, EntityManagerInterface $entity_manager, CacheBackendInterface $cache, LanguageManagerInterface $language_manager, CacheBackendInterface $static_cache = NULL) {
+    // @todo Remove this line in Drupal 9.0.x and make $static_cache required.
     $static_cache = isset($static_cache) ? $static_cache : \Drupal::service('entity.static_cache');
     parent::__construct($entity_type, $entity_manager, $cache, $static_cache);
     $this->database = $database;