How can I add labels to fcm_options?

[iiii4966]

The push is being sent through the gcm device in this module.
But as the title says, when send push, need to add lable to fcm_options to track.
If look at the internal code, The analyticsLabel key I need does not exist.
fcm

FCM_OPTIONS_KEYS = [
	"collapse_key", "priority", "content_available", "delay_while_idle", "time_to_live",
	"restricted_package_name", "dry_run"
]

Can I add it temporarily or add it?

{
   "message":{
      "data":{
         
      },
      "fcmOptions":{
         "analyticsLabel":"HelloWorld" <- this!!
      },
      "notification":{
         "body":"Hello world"
      },
      "token":"token"
   },
   "validateOnly":false
}

[jamaalscarlett]

@iiii4966 The analyticsLabel is part of the v1 api that is not yet fully supported. See #546