Fix for issue 8311.

tests/lib/async/stream_transform_test.dart

Index: tests/lib/async/stream_transform_test.dart
diff --git a/tests/lib/async/stream_transform_test.dart b/tests/lib/async/stream_transform_test.dart
index 436c229d5d5974c51b7257928baafd99b52eb6a0..abd6f53d3c8d62b8a2bcd46cb5c6a20cd3767084 100644
--- a/tests/lib/async/stream_transform_test.dart
+++ b/tests/lib/async/stream_transform_test.dart
@@ -10,7 +10,7 @@ import 'event_helper.dart';
 
 
 main() {
-  // Regression tests for http://dartbug.com/8311
+  // Regression tests for http://dartbug.com/8310 and 8311
 
   test("simpleDone", () {
     StreamController c = new StreamController();
@@ -45,4 +45,17 @@ main() {
     input.replay(c);
     actual.resume();
   });
+
+  test("closing after done", () {
+    var controller = new StreamController();
+    var buffer = new StringBuffer();
+    controller.stream.map((e) => e).transform(new StreamTransformer(
+        handleData: (element, sink) { sink.add(element); },
+        handleDone: (sink) { sink.close(); })
+    ).listen(expectAsync1((e) => expect(e, equals("foo"))));
+
+    controller.add("foo");
+    // Should not crash.
+    controller.close();
+  });
 }