title: Firebase SDK Not opening launcher activity when app is background
body: <p>I am using Firebase-SDK for sending push messages to my application.after processing two or three push notification events when I send third or fourth push to a device with the app in background mode, then on Tapping, notification it resumes that background activity instead of launching default launcher activity.is this bug in firebase-SDK. I am using firebase version 9.8.0.</p>
  
  <p><strong>Steps to reproduce.</strong></p>
  
  <p>kill the app and send push it is redirecting to desired activity after processing this push put app in background and send push. it will resume last activity with intent extras as null.</p>