When a user gets "cancelled reassign" uid's in the table file_managed don't get updated to the new uid (0) making them orphaned

The approach was already validated before in #14 and I think this looks good as well, this has enough test coverage as well.

I was doubting if the hook was the right place or if we should do it where the user actually gets removed, but I think this is better so that it all sticks in the file module.

No longer applies.

Fix looks good though

+++ b/core/modules/file/tests/src/Functional/FileListingTest.php
@@ -214,6 +217,57 @@ public function testFileListingUsageNoLink() {
+    // Create node entity and attach the created file.
+    $node = $this->drupalCreateNode(['type' => 'article', 'file' => $file]);
+    $node->save();

Why do we create a node and an entity to attach the file to?

Isn't one (the entity test entity) enough?