add Reflect.global

Author: guybedford

lib/loader.js

@@ -1129,6 +1129,7 @@ function logloads(loads) {
 
     __global.Reflect = __global.Reflect || {};
     __global.Reflect.Loader = __global.Reflect.Loader || Loader;
+    __global.Reflect.global = __global.Reflect.global || __global;
     __global.LoaderPolyfill = Loader;
 
   })();