fix to run against latest analyzer

lib/runtime/dart/_isolate_helper.js

Index: lib/runtime/dart/_isolate_helper.js
diff --git a/lib/runtime/dart/_isolate_helper.js b/lib/runtime/dart/_isolate_helper.js
index a482f2149f739ed67fa0f17cc4c76abd52823677..abeb5e62f0fd254e65a9adc3fc59d5d95f4f7ffb 100644
--- a/lib/runtime/dart/_isolate_helper.js
+++ b/lib/runtime/dart/_isolate_helper.js
@@ -756,7 +756,8 @@ dart_library.library('dart/_isolate_helper', null, /* Imports */[
       exports._globalState.isolates[dartx.remove](this.id);
       this.errorPorts.clear();
       if (this.doneHandlers != null) {
-        for (let port of dart.as(this.doneHandlers, core.Iterable$(isolate.SendPort))) {
+        for (let port of dart.as(this.doneHandlers, core.Iterable)) {
+          dart.as(port, isolate.SendPort);
           port.send(null);
         }
         this.doneHandlers = null;