Remove MigrateEntityDestinationFieldInterface

Looks good to me.

+++ b/core/modules/migrate/src/Plugin/migrate/destination/EntityContentBase.php
@@ -76,27 +73,6 @@ public static function create(ContainerInterface $container, array $configuratio
-    if ($bundle_key = $this->getKey('bundle')) {
-      $bundle = $row->getDestinationProperty($bundle_key);
-    }
-    else {
-      $bundle = $this->storage->getEntityTypeId();
-    }
-    // Some migrations save additional data of an existing entity and only
-    // provide the reference to the entity, in those cases, we can not run the
-    // processing below. Migrations that need that need to provide the bundle.
-    if ($bundle) {
-      $field_definitions = $this->entityManager->getFieldDefinitions($this->storage->getEntityTypeId(), $bundle);
-      foreach ($field_definitions as $field_name => $field_definition) {
-        $field_type = $field_definition->getType();
-        if ($this->migrateEntityFieldPluginManager->getDefinition($field_type, FALSE)) {
-          $destination_value = $this->migrateEntityFieldPluginManager->createInstance($field_type)->import($field_definition, $row->getDestinationProperty($field_name));
-          // @TODO: check for NULL return? Add an unset to $row? Maybe needed in
-          // exception handling? Propagate exception?
-          $row->setDestinationProperty($field_name, $destination_value);
-        }
-      }
-    }

Wow, this is great!

Yay less code!

Committed and pushed to 8.x. Thanks!