initial sync*, part of #221

test/codegen/expect/syncstar_syntax.js

+dart_library.library('syncstar_syntax', null, /* Imports */[
+  "dart_runtime/dart",
+  'dart/core'
+], /* Lazy imports */[
+], function(exports, dart, core) {
+  'use strict';
+  let dartx = dart.dartx;
+  function* foo() {
+    yield 1;
+    yield* dart.list([2, 3], core.int);
+  }
+  dart.fn(foo, core.Iterable$(core.int), []);
+  class Class extends core.Object {
+    *bar() {
+      yield 1;
+      yield* dart.list([2, 3], core.int);
+    }
+    static *baz() {
+      yield 1;
+      yield* dart.list([2, 3], core.int);
+    }
+  }
+  dart.setSignature(Class, {
+    methods: () => ({bar: [core.Iterable$(core.int), []]}),
+    statics: () => ({baz: [core.Iterable$(core.int), []]}),
+    names: ['baz']
+  });
+  function main() {
+    function* qux() {
+      yield 1;
+      yield* dart.list([2, 3], core.int);
+    }
+    dart.fn(qux, core.Iterable$(core.int), []);
+    foo()[dartx.forEach](core.print);
+    new Class().bar()[dartx.forEach](core.print);
+    Class.baz()[dartx.forEach](core.print);
+    qux()[dartx.forEach](core.print);
+  }
+  dart.fn(main);
+  // Exports:
+  exports.foo = foo;
+  exports.Class = Class;
+  exports.main = main;
+});