fixes #206, add checking for unary ops

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 14722e3181c4603cb15f0fe68a5e018dec8ac9cb..35e5763118fc0363f22360810b54eccde7ef831b 100644
--- a/lib/runtime/dart/_isolate_helper.js
+++ b/lib/runtime/dart/_isolate_helper.js
@@ -589,7 +589,7 @@ var async = dart.import(async);
       if (this.doneHandlers == null) {
         this.doneHandlers = [];
       }
-      if (dart.dsend(this.doneHandlers, 'contains', responsePort))
+      if (dart.as(dart.dsend(this.doneHandlers, 'contains', responsePort), core.bool))

[vsm, 2015/06/04 17:07:32]

We'll need a null check here as well.

[Jennifer Messerly, 2015/06/04 21:54:18]

Done.

         return;
       dart.dsend(this.doneHandlers, 'add', responsePort);
     }
@@ -689,7 +689,7 @@ var async = dart.import(async);
         if (old != null)
           old[_setGlobals]();
         if (this[_scheduledControlEvents] != null) {
-          while (dart.dload(this[_scheduledControlEvents], 'isNotEmpty')) {
+          while (dart.as(dart.dload(this[_scheduledControlEvents], 'isNotEmpty'), core.bool)) {
             dart.dcall(dart.dsend(this[_scheduledControlEvents], 'removeFirst'));
           }
         }