Declare support for async 2.0.0 (dart-lang/stream_channel#10)

pkgs/stream_channel/CHANGELOG.md

diff --git a/pkgs/stream_channel/CHANGELOG.md b/pkgs/stream_channel/CHANGELOG.md
index 8d44b21..a1cf9ed 100644
--- a/pkgs/stream_channel/CHANGELOG.md
+++ b/pkgs/stream_channel/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 1.6.2
+
+* Declare support for `async` 2.0.0.
+
 ## 1.6.1
 
 * Fix the type of `StreamChannel.transform()`. This previously inverted the

pkgs/stream_channel/pubspec.yaml

diff --git a/pkgs/stream_channel/pubspec.yaml b/pkgs/stream_channel/pubspec.yaml
index 2d86362..fee6433 100644
--- a/pkgs/stream_channel/pubspec.yaml
+++ b/pkgs/stream_channel/pubspec.yaml
@@ -1,12 +1,12 @@
 name: stream_channel
-version: 1.6.2-dev
+version: 1.6.2
 description: An abstraction for two-way communication channels.
 author: Dart Team <misc@dartlang.org>
 homepage: https://github.com/dart-lang/stream_channel
 environment:
   sdk: '>=1.21.0 <2.0.0'
 dependencies:
-  async: '^1.11.0'
+  async: '>=1.11.0 <3.0.0'
   stack_trace: '^1.0.0'
 dev_dependencies:
   test: '^0.12.18'