title: JSOM SharePoint 2013 Error while getting WorkflowSubscription
body: <p>I was following the instruction from msdn to get WorkflowSubscriptionService over JSOM.</p>
  
  <p>Working with the SharePoint 2013 Workflow Services Client Side Object Model:
  <a href="http://msdn.microsoft.com/en-us/library/office/dn481315(v=office.15).aspx" rel="nofollow">http://msdn.microsoft.com/en-us/library/office/dn481315(v=office.15).aspx</a></p>
  
  <pre><code>var clientContext = SP.ClientContext.get_current();
  var workflowServicesManager = SP.WorkflowServices.WorkflowServicesManager.newObject(clientContext, clientContext.get_web()); 
  var workflowSubscriptionService = workflowServicesManager.getWorkflowSubscriptionService();
  </code></pre>
  
  <p>These three lines always throw a error:
  TypeError: Object [object Object] has no method 'get_context'
  message: "Object [object Object] has no method 'get_context'"
  stack: (...)
  get stack: function () { [native code] }
  set stack: function () { [native code] }
  <strong>proto</strong>: Error</p>
  
  <p>I can't find a mistake. Is this a known bug?</p>