Move runtime js files down to lib/runtime/dart

lib/runtime/dart/_types.js

Index: lib/runtime/dart/_types.js
diff --git a/lib/runtime/_types.js b/lib/runtime/dart/_types.js
similarity index 99%
rename from lib/runtime/_types.js
rename to lib/runtime/dart/_types.js
index 8c8122e7e47d258b59db5637d19b6e6131b52854..225153813c667e02a86bd26e90be98ce5d64d52f 100644
--- a/lib/runtime/_types.js
+++ b/lib/runtime/dart/_types.js
@@ -5,11 +5,11 @@
 /* This library defines the representation of runtime types.
 */
 
-dart_library.library('dart_runtime/_types', null, /* Imports */[
+dart_library.library('dart/_types', null, /* Imports */[
 ], /* Lazy Imports */[
   'dart/core',
-  'dart_runtime/_classes',
-  'dart_runtime/_rtti'
+  'dart/_classes',
+  'dart/_rtti'
 ], function(exports, core, classes, rtti) {
   'use strict';