fixes #131, use before define from variables to classes

lib/runtime/dart/_isolate_helper.js

 var _isolate_helper = dart.defineLibrary(_isolate_helper, {});
 var core = dart.import(core);
 var _native_typed_data = dart.import(_native_typed_data);
 var _interceptors = dart.lazyImport(_interceptors);
 var _js_helper = dart.lazyImport(_js_helper);
 var isolate = dart.import(isolate);
 var _foreign_helper = dart.import(_foreign_helper);
 var _js_embedded_names = dart.import(_js_embedded_names);
 var collection = dart.import(collection);
 var async = dart.import(async);
@@ skipping 338 matching lines @@
       let classId = dart.as(dart.dindex(x, 1), core.String);
       let fields = dart.as(dart.dindex(x, 2), core.List);
       let instanceFromClassId = _foreign_helper.JS_EMBEDDED_GLOBAL('', _js_embedded_names.INSTANCE_FROM_CLASS_ID);
       let initializeObject = _foreign_helper.JS_EMBEDDED_GLOBAL('', _js_embedded_names.INITIALIZE_EMPTY_INSTANCE);
       let emptyInstance = instanceFromClassId(classId);
       this.deserializedObjects[core.$add](emptyInstance);
       this.deserializeArrayInPlace(dart.as(fields, _interceptors.JSArray));
       return initializeObject(classId, emptyInstance, fields);
     }
   }
-  let __CastType0 = dart.typedef('__CastType0', () => dart.functionType(dart.dynamic, [dart.dynamic]));
+  let __CastType0 = dart.typedef('__CastType0', dart.functionType(dart.dynamic, [dart.dynamic]));
   // Function _callInIsolate: (_IsolateContext, Function) → dynamic
   function _callInIsolate(isolate, func) {
     let result = isolate.eval(func);
     exports._globalState.topEventLoop.run();
     return result;
   }
   let _activeJsAsyncCount = Symbol('_activeJsAsyncCount');
   // Function enterJsAsync: () → dynamic
   function enterJsAsync() {
     let o = exports._globalState.topEventLoop;
@@ skipping 463 matching lines @@
     },
     get globalWorker() {
       _js_helper.requiresPreamble();
       return self.Worker;
     },
     get globalPostMessageDefined() {
       _js_helper.requiresPreamble();
       return !!self.postMessage;
     }
   });
-  let _MainFunction = dart.typedef('_MainFunction', () => dart.functionType(dart.dynamic, []));
-  let _MainFunctionArgs = dart.typedef('_MainFunctionArgs', () => dart.functionType(dart.dynamic, [dart.dynamic]));
-  let _MainFunctionArgsMessage = dart.typedef('_MainFunctionArgsMessage', () => dart.functionType(dart.dynamic, [dart.dynamic, dart.dynamic]));
+  let _MainFunction = dart.typedef('_MainFunction', dart.functionType(dart.dynamic, []));
+  let _MainFunctionArgs = dart.typedef('_MainFunctionArgs', dart.functionType(dart.dynamic, [dart.dynamic]));
+  let _MainFunctionArgsMessage = dart.typedef('_MainFunctionArgsMessage', dart.functionType(dart.dynamic, [dart.dynamic, dart.dynamic]));
   class IsolateNatives extends core.Object {
     static computeThisScript() {
       let currentScript = _foreign_helper.JS_EMBEDDED_GLOBAL('', _js_embedded_names.CURRENT_SCRIPT);
       if (currentScript != null) {
         return String(currentScript.src);
       }
       if (_js_helper.Primitives.isD8)
         return IsolateNatives.computeThisScriptD8();
       if (_js_helper.Primitives.isJsshell)
         return IsolateNatives.computeThisScriptJsshell();
@@ skipping 531 matching lines @@
   exports.leaveJsAsync = leaveJsAsync;
   exports.isWorker = isWorker;
   exports.startRootIsolate = startRootIsolate;
   exports.IsolateNatives = IsolateNatives;
   exports.RawReceivePortImpl = RawReceivePortImpl;
   exports.ReceivePortImpl = ReceivePortImpl;
   exports.TimerImpl = TimerImpl;
   exports.hasTimer = hasTimer;
   exports.CapabilityImpl = CapabilityImpl;
 })(_isolate_helper, core, _native_typed_data, _interceptors, _js_helper, isolate, _foreign_helper, _js_embedded_names, collection, async);