Fixes #178

lib/runtime/dart/core.js

 var core = dart.defineLibrary(core, {});
 var _js_helper = dart.lazyImport(_js_helper);
 var _internal = dart.lazyImport(_internal);
 var collection = dart.lazyImport(collection);
 var _interceptors = dart.lazyImport(_interceptors);
 var convert = dart.lazyImport(convert);
 (function(exports, _js_helper, _internal, collection, _interceptors, convert) {
   'use strict';
   class Object {
     constructor() {
@@ skipping 1324 matching lines @@
           }
         }
       }
       [$map](f) {
         dart.as(f, dart.functionType(dart.dynamic, [E]));
         return _internal.IterableMixinWorkaround.mapList(this, f);
       }
       [$join](separator) {
         if (separator === void 0)
           separator = "";
-        let list = new List(this[$length]);
+        let list = new (List$(dart.dynamic))(this[$length]);
         for (let i = 0; dart.notNull(i) < dart.notNull(this[$length]); i = dart.notNull(i) + 1) {
           list[$set](i, `${this[$get](i)}`);
         }
         return list.join(separator);
       }
       [$take](n) {
         return new (_internal.IterableMixinWorkaround$(E))().takeList(this, n);
       }
       [$takeWhile](test) {
         dart.as(test, dart.functionType(bool, [E]));
@@ skipping 2129 matching lines @@
   exports.Stopwatch = Stopwatch;
   exports.String = String;
   exports.RuneIterator = RuneIterator;
   exports.StringBuffer = StringBuffer;
   exports.StringSink = StringSink;
   exports.Symbol = Symbol;
   exports.Type = Type;
   exports.Uri = Uri;
   exports.SupportJsExtensionMethods = SupportJsExtensionMethods;
 })(core, _js_helper, _internal, collection, _interceptors, convert);