title: Angular 4 put a global constant available to zone.js
body: <p>i am using Angular (4 i think) with typescript and zone.js (0.8.4). I import zone.js via the "polyfills.ts" file. When I look inside the source code of zone.js, there is code like this:</p>
  
  <pre><code>var isDisableIECheck = _global['__Zone_disable_IE_check'] || false;
  </code></pre>
  
  <p>My question is, how can I set this variable in _globals ?</p>
  
  <p>Thanks</p>