[release] Add release notes for 2.9.1
Change-Id: I8d3ea79f2d0e027ab5834b332a8d63868b7cad2a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/158281
Reviewed-by: Johnni Winther <johnniwinther@google.com>
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 725055b..bbd8830 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,4 +1,11 @@
-## 2.9.0
+## 2.9.1 - 2020-08-12
+
+This is a patch release that fixes unhandled exceptions in some Flutter
+applications (issue [flutter/flutter#63038][]).
+
+[flutter/flutter#63038]: https://github.com/flutter/flutter/issues/63038
+
+## 2.9.0 - 2020-08-05
### Language
