Redo StreamTransformers so they work with Stack traces.

tests/lib/async/catch_errors16_test.dart

Index: tests/lib/async/catch_errors16_test.dart
diff --git a/tests/lib/async/catch_errors16_test.dart b/tests/lib/async/catch_errors16_test.dart
index e2af7686f34c1ce24a2a5091fb7970fe486286b8..0b939c4c9c0d47cfb4ca8bb294351a4e20460e44 100644
--- a/tests/lib/async/catch_errors16_test.dart
+++ b/tests/lib/async/catch_errors16_test.dart
@@ -19,8 +19,8 @@ main() {
     stream = stream.map((x) => x + 100);
   }).listen((x) { events.add(x); });
   stream
-    .transform(new StreamTransformer(
-        handleError: (e, sink) => sink.add("error $e")))
+    .transform(new StreamTransformer.fromHandlers(
+        handleError: (e, st, sink) => sink.add("error $e")))
     .listen((x) { events.add("stream $x"); },
             onDone: () {
               Expect.listEquals(["stream 101",