title: Angular 5 Testing: Expected to be running in 'ProxyZone', but it was not found
body: <p>I have created a new Angular 5 project using Angular cli. When I run the default test, I get the following error:</p>
  
  <pre><code>Error: Expected to be running in 'ProxyZone', but it was not found.
  at Function.webpackJsonp.../../../../zone.js/dist/proxy.js.ProxyZoneSpec.assertPresent (http://localhost:9876/_karma_webpack_/webpack:/home/sukumar/workspace/bizAnalyst/partnerportal/node_modules/zone.js/dist/proxy.js:38:1)
  </code></pre>
  
  <p>How to rectify this issue?</p>
  
  <p>P.S.: Angular version: 5.2.1</p>