feat(zone): add initial implementation of VmTurnZone

modules/facade/src/async.dart

@@ -20,4 +20,17 @@ class PromiseWrapper {
     if (success == null) return promise.catchError(onError);
     return promise.then(success, onError: onError);
   }
+
+  static completer(){
+    return new _Completer(new Completer());
+  }
+}
+
+class _Completer {
+  Completer c;
+  _Completer(this.c);
+
+  get promise => c.future;
+  get complete => c.complete;
+
 }

modules/facade/src/async.es6

@@ -17,4 +17,20 @@ export class PromiseWrapper {
   static then(promise:Promise, success:Function, rejection:Function):Promise {
     return promise.then(success, rejection);
   }
+
+  static completer() {
+    var resolve;
+    var reject;
+
+    var p = new Promise(function(res, rej) {
+      resolve = res;
+      reject = rej;
+    });
+
+    return {
+      promise: p,
+      complete: resolve,
+      reject: reject
+    };
+  }
 }

modules/facade/src/collection.dart

@@ -97,6 +97,7 @@ class ListWrapper {
   static void insert(List l, int index, value) { l.insert(index, value); }
   static void removeAt(List l, int index) { l.removeAt(index); }
   static void clear(List l) { l.clear(); }
+  static String join(List l, String s) => l.join(s);
 }
 
 bool isListLikeIterable(obj) => obj is Iterable;

modules/facade/src/collection.es6

@@ -121,11 +121,16 @@ export class ListWrapper {
     list.splice(index, 0, value);
   }
   static removeAt(list, index:int) {
+    var res = list[index];
     list.splice(index, 1);
+    return res;
   }
   static clear(list) {
     list.splice(0, list.length);
   }
+  static join(list, s) {
+    return list.join(s);
+  }
 }
 
 export function isListLikeIterable(obj):boolean {