diff --git a/core/lib/Drupal/Core/Entity/EntityStorageBase.php b/core/lib/Drupal/Core/Entity/EntityStorageBase.php
index b8f98d0..5d2c2aa 100644
--- a/core/lib/Drupal/Core/Entity/EntityStorageBase.php
+++ b/core/lib/Drupal/Core/Entity/EntityStorageBase.php
@@ -460,6 +460,8 @@ public function loadByProperties(array $values = array()) {
    * {@inheritdoc}
    */
   public function getQuery($conjunction = 'AND') {
+    // Access the service directly rather than entity.query factory so the
+    // storage's current entity type is used.
     return \Drupal::service($this->getQueryServicename())->get($this->entityType, $conjunction);
   }
 
diff --git a/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorageSchema.php b/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorageSchema.php
index 0b1aeb9..d3087b7 100644
--- a/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorageSchema.php
+++ b/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorageSchema.php
@@ -178,10 +178,13 @@ public function requiresFieldStorageSchemaChanges(FieldStorageDefinitionInterfac
    * {@inheritdoc}
    */
   public function requiresEntityDataMigration(EntityTypeInterface $entity_type, EntityTypeInterface $original) {
+    // If the original storage has existing entities, or it is impossible to
+    // determine if that is the case, require entity data to be migrated.
     $original_storage_class = $original->getStorageClass();
     if (!class_exists($original_storage_class)) {
       return TRUE;
     }
+    // Use the original entity type since the storage has not been updated.
     $original_storage = $this->entityManager->createHandlerInstance($original_storage_class, $original);
     return $original_storage->hasData();
   }