Add an impl for ThreadId

Summary: Useful in a project I was working on.

Reviewed By: stepancheg

Differential Revision: D66030834

fbshipit-source-id: 2b50cb0aa52eeeebf5968b6de5c81680b8f3c1dc

allocative/allocative/src/impls/std/thread.rs

@@ -0,0 +1,19 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under both the MIT license found in the
+ * LICENSE-MIT file in the root directory of this source tree and the Apache
+ * License, Version 2.0 found in the LICENSE-APACHE file in the root directory
+ * of this source tree.
+ */
+
+use std::thread::ThreadId;
+
+use crate::allocative_trait::Allocative;
+use crate::visitor::Visitor;
+
+impl Allocative for ThreadId {
+    fn visit<'a, 'b: 'a>(&self, visitor: &'a mut Visitor<'b>) {
+        visitor.enter_self_sized::<Self>().exit();
+    }
+}