title: FCM token missing
body: <p>I'm trying to test FCM using Postman, but I always get the following error even the FCM token is there. I got the token in the Cloud Messaging tab: Firebase Cloud Messaging token.</p>
  
  <pre><code>&lt;HTML&gt;
  &lt;HEAD&gt;
      &lt;TITLE&gt;The request was missing an Authentification Key (FCM Token). Please, refer to section &amp;quot;Authentification&amp;quot; of the FCM documentation, at https://firebase.google.com/docs/cloud-messaging/server.&lt;/TITLE&gt;
  &lt;/HEAD&gt;
  </code></pre>
  
  <p>Here is what I send.</p>
  
  <pre><code>POST /fcm/send HTTP/1.1
  Host: fcm.googleapis.com
  Cache-Control: no-cache
  Postman-Token: 9109eb13-245f-0786-21a5-6207f5426b44
  
  Content-Type:application/json
  Authorization:key=AAAAfnYrKvU:APA91bFwgeM3zuFId6UDzvIHk9qZ3lKHnX-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
  {  "data": {     "message": "This is a Firebase Cloud Messaging Topic Message!",    } }:
  </code></pre>