Stop using comment-based generic syntax (#3)

Closes #2
diff --git a/CHANGELOG.md b/CHANGELOG.md
index d67f46a..d85c3d0 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 0.2.2
+
+* Stop using comment-based generic syntax.
+
 ## 0.2.1
 
 * Fix all strong-mode warnings.
diff --git a/lib/src/web_socket_handler.dart b/lib/src/web_socket_handler.dart
index 73dcfef..266a9dc 100644
--- a/lib/src/web_socket_handler.dart
+++ b/lib/src/web_socket_handler.dart
@@ -66,7 +66,7 @@
 
     var protocol = _chooseProtocol(request);
     request.hijack((untypedChannel) {
-      var channel = (untypedChannel as StreamChannel).cast/*<List<int>>*/();
+      var channel = (untypedChannel as StreamChannel).cast<List<int>>();
 
       var sink = UTF8.encoder.startChunkedConversion(channel.sink);
       sink.add(
diff --git a/pubspec.yaml b/pubspec.yaml
index f663cdb..1707f66 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
 name: shelf_web_socket
-version: 0.2.1
+version: 0.2.2
 author: "Dart Team <misc@dartlang.org>"
 homepage: http://github.com/dart-lang/shelf_web_socket
 description: >
@@ -12,4 +12,4 @@
   http: ">=0.10.0 <0.12.0"
   test: "^0.12.0"
 environment:
-  sdk: ">=1.8.0 <2.0.0"
+  sdk: ">=1.21.0 <2.0.0"