title: After updating Google play services to 8.4.0 push notifications displayed by themselves
body: <p>For Push notifications we are using GCM(Google Cloud Messaging). It was working fine when we used play-services:8.3.0 . We process push notifications with our own receiver. After upgrading to <code>com.google.android.gms:play-services:8.4.0</code>
  Push not coming to my myGcmListenerService, instead its shown by itself in notification bar. Also it shows this error in Log 
  <code>GcmAnalytics: Error while parsing timestamp in GCM event.</code></p>
  
  <p>With 8.3.0 we received push like this:
  <code>
  Bundle[{gcm.notification.e=1, google.c.a.ts=234343426, gcm.notification.badge=1, gcm.notification.sound=default, gcm.notification.sound2=default, gcm.notification.body=John M @ Cords, Wires And Cable Ftu, gcm.notification.data={"name":"new_chat_message","message_id":490666,"channel_id":5366}, google.c.a.e=1, collapse_key=com.domain.app.debug}]</code></p>
  
  <p>With 8.4.0 pushes coming like this:
  <code>
  Bundle[{notification=Bundle[{sound2=default, e=1, body=John M @ Cords, Wires And Cable Rrr, data={"name":"new_chat_message","message_id":490641,"channel_id":5366}, badge=1, sound=default}], collapse_key=com.domain.app.debug}]</code></p>