fixes #177, FunctionDeclarationStatement and closing over `this`

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 537 matching lines @@
       if (!dart.equals(this.terminateCapability, authentification))
         return;
       this.errorsAreFatal = errorsAreFatal;
     }
     handlePing(responsePort, pingType) {
       if (pingType == isolate.Isolate.IMMEDIATE || pingType == isolate.Isolate.BEFORE_NEXT_EVENT && !dart.notNull(this[_isExecutingEvent])) {
         responsePort.send(null);
         return;
       }
       // Function respond: () → void
-      function respond() {
+      let respond = () => {
         responsePort.send(null);
-      }
+      };
       if (pingType == isolate.Isolate.AS_EVENT) {
         exports._globalState.topEventLoop.enqueue(this, respond, "ping");
         return;
       }
       dart.assert(pingType == isolate.Isolate.BEFORE_NEXT_EVENT);
       if (this[_scheduledControlEvents] == null) {
         this[_scheduledControlEvents] = new collection.Queue();
       }
       dart.dsend(this[_scheduledControlEvents], 'addLast', respond);
     }
@@ skipping 201 matching lines @@
         this.checkOpenReceivePortsFromCommandLine();
         exports._globalState.maybeCloseWorker();
         return false;
       }
       event.process();
       return true;
     }
     [_runHelper]() {
       if (exports.globalWindow != null) {
         // Function next: () → void
-        function next() {
+        let next = (() => {
           if (!dart.notNull(this.runIteration()))
             return;
           async.Timer.run(next);
-        }
+        }).bind(this);
         next();
       } else {
         while (this.runIteration()) {
         }
       }
     }
     run() {
       if (!dart.notNull(exports._globalState.isWorker)) {
         this[_runHelper]();
       } else {
@@ skipping 255 matching lines @@
     }
     static get currentIsolate() {
       let context = dart.as(_foreign_helper.JS_CURRENT_ISOLATE_CONTEXT(), _IsolateContext);
       return new isolate.Isolate(context.controlPort.sendPort, {pauseCapability: context.pauseCapability, terminateCapability: context.terminateCapability});
     }
     static _startIsolate(topLevel, args, message, isSpawnUri, startPaused, replyTo) {
       let context = dart.as(_foreign_helper.JS_CURRENT_ISOLATE_CONTEXT(), _IsolateContext);
       _js_helper.Primitives.initializeStatics(context.id);
       replyTo.send([_SPAWNED_SIGNAL, context.controlPort.sendPort, context.pauseCapability, context.terminateCapability]);
       // Function runStartFunction: () → void
-      function runStartFunction() {
+      let runStartFunction = () => {
         context.initialized = true;
         if (!dart.notNull(isSpawnUri)) {
           dart.dcall(topLevel, message);
         } else if (dart.is(topLevel, _MainFunctionArgsMessage)) {
           dart.dcall(topLevel, args, message);
         } else if (dart.is(topLevel, _MainFunctionArgs)) {
           dart.dcall(topLevel, args);
         } else {
           dart.dcall(topLevel);
         }
-      }
+      };
       if (startPaused) {
         context.addPause(context.pauseCapability, context.pauseCapability);
         exports._globalState.topEventLoop.enqueue(context, runStartFunction, 'start isolate');
       } else {
         runStartFunction();
       }
     }
     static _spawnWorker(functionName, uri, args, message, isSpawnUri, startPaused, replyPort, onError) {
       if (uri == null)
         uri = IsolateNatives.thisScript;
@@ skipping 199 matching lines @@
   let _once = Symbol('_once');
   let _inEventLoop = Symbol('_inEventLoop');
   let _handle = Symbol('_handle');
   class TimerImpl extends core.Object {
     TimerImpl(milliseconds, callback) {
       this[_once] = true;
       this[_inEventLoop] = false;
       this[_handle] = null;
       if (milliseconds == 0 && (!dart.notNull(hasTimer()) || dart.notNull(exports._globalState.isWorker))) {
         // Function internalCallback: () → void
-        function internalCallback() {
+        let internalCallback = (() => {
           this[_handle] = null;
           callback();
-        }
+        }).bind(this);
         this[_handle] = 1;
         exports._globalState.topEventLoop.enqueue(exports._globalState.currentContext, internalCallback, 'timer');
         this[_inEventLoop] = true;
       } else if (hasTimer()) {
         // Function internalCallback: () → void
-        function internalCallback() {
+        let internalCallback = (() => {
           this[_handle] = null;
           leaveJsAsync();
           callback();
-        }
+        }).bind(this);
         enterJsAsync();
         this[_handle] = self.setTimeout(_js_helper.convertDartClosureToJS(internalCallback, 0), milliseconds);
       } else {
         dart.assert(dart.notNull(milliseconds) > 0);
         throw new core.UnsupportedError("Timer greater than 0.");
       }
     }
     periodic(milliseconds, callback) {
       this[_once] = false;
       this[_inEventLoop] = false;
@@ skipping 70 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);