Enable DDC output to run on v8/d8 using ES6 modules

pkg/dev_compiler/tool/input_sdk/private/ddc_runtime/runtime.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library dart._runtime;
 
 import 'dart:async';
 import 'dart:collection';
 
 import 'dart:_foreign_helper' show JS, JSExportName, rest, spread;
@@ skipping 64 matching lines @@
       if (typeof Animation == "undefined") {
         let d = document.createElement('div');
         if (typeof d.animate != "undefined") {
           window.Animation = d.animate(d).constructor;
         }
       }
       if (typeof SourceBufferList == "undefined") {
         window.SourceBufferList = new MediaSource().sourceBuffers.constructor;
       }
     }
-    return typeof window == "undefined" ? global : window;
+    var globalState = (typeof window != "undefined") ? window
+      : (typeof global != "undefined") ? global
+      : (typeof self != "undefined") ? self : {};
+    return globalState;
   }()
 ''');
 
 final JsSymbol = JS('', 'Symbol');