follow up for #25578, add `@checked` to package:meta

pkg/meta/CHANGELOG.md

Index: pkg/meta/CHANGELOG.md
diff --git a/pkg/meta/CHANGELOG.md b/pkg/meta/CHANGELOG.md
index 4a462d7e58e72e72d9b6cd3b871f169236347226..11e1a69c81cf99fc827820245f0e54edc6462a81 100644
--- a/pkg/meta/CHANGELOG.md
+++ b/pkg/meta/CHANGELOG.md
@@ -1,3 +1,23 @@
+## 1.0.3
+* Introduce `@checked` to override a method and tighten a parameter
+    type (SDK issue [25578](https://github.com/dart-lang/sdk/issues/25578)).
+
+    ```dart
+    import 'package:meta/meta.dart' show checked;
+    class View {
+      addChild(View v) {}
+    }
+    class MyView extends View {
+      // this override is legal, it will check at runtime if we actually
+      // got a MyView.
+      addChild(@checked MyView v) {}
+    }
+    main() {
+      dynamic mv = new MyView();
+      mv.addChild(new View()); // runtime error
+    }
+    ```
+
 ## 1.0.2
 * Introduce `@visibleForTesting` annotation for declarations that may be referenced only in the library or in a test.