Do not suppress implicit constructors that need a super call.

lib/runtime/dart/async.js

Index: lib/runtime/dart/async.js
diff --git a/lib/runtime/dart/async.js b/lib/runtime/dart/async.js
index dab5c9170f90084c29f55e44b4ef04b73c53da67..1c4924d884b76e55d667f79bb865e64e30b81e03 100644
--- a/lib/runtime/dart/async.js
+++ b/lib/runtime/dart/async.js
@@ -818,6 +818,9 @@ var async;
   let Stream = Stream$();
   let _StreamImpl$ = dart.generic(function(T) {
     class _StreamImpl extends Stream$(T) {
+      _StreamImpl() {
+        super.Stream();
+      }
       listen(onData, opts) {
         dart.as(onData, dart.functionType(dart.void, [T]));
         let onError = opts && 'onError' in opts ? opts.onError : null;
@@ -1989,6 +1992,9 @@ var async;
   let _asyncCompleteError = Symbol('_asyncCompleteError');
   let _AsyncCompleter$ = dart.generic(function(T) {
     class _AsyncCompleter extends _Completer$(T) {
+      _AsyncCompleter() {
+        super._Completer();
+      }
       complete(value) {
         if (value === void 0)
           value = null;
@@ -2005,6 +2011,9 @@ var async;
   let _AsyncCompleter = _AsyncCompleter$();
   let _SyncCompleter$ = dart.generic(function(T) {
     class _SyncCompleter extends _Completer$(T) {
+      _SyncCompleter() {
+        super._Completer();
+      }
       complete(value) {
         if (value === void 0)
           value = null;