[READ] Step 1: Are you in the right place?

• For issues or feature requests related to the code in this repository
  file a Github issue.
  • If this is a feature request make sure the issue title starts with "FR:".
• For general technical questions, post a question on StackOverflow
  with the firebase tag.
• For general Firebase discussion, use the firebase-talk
  google group.
• For help troubleshooting your application that does not fall under one
  of the above categories, reach out to the personalized
  Firebase support channel.

[REQUIRED] Step 2: Describe your environment

• Xcode version: 10.2
• Firebase SDK version: 6.0.0
• Firebase Component: Core
• Component version: 6.0.0

[REQUIRED] Step 3: Describe the problem

Getting crash when calling FirebaseApp.configure() in willFinishLaunchingWithOptions

Steps to reproduce:

What happened? How can we make the problem occur?
This is happening when running in iOS simulator.
It occurs after running the app, then deleting app from simulator and running again.
It is intermittently reproducible.

Fatal Exception: NSInternalInconsistencyException
Cannot fetch token invalid checkin state

Fatal Exception: NSInternalInconsistencyException
0 CoreFoundation 0x113e9f1a3 (Missing)
1 libobjc.A.dylib 0x112e0b735 objc_exception_throw
2 CoreFoundation 0x113e9ef42 (Missing)
3 Foundation 0x11158f940 -[NSAssertionHandler handleFailureInFunction:file:lineNumber:description:]
4 mpdx-ios 0x10f04dd03 -[FIRInstanceIDTokenOperation start] (FIRInstanceIDTokenOperation.m:136)
5 Foundation 0x1115fcc4b __NSOQSchedule_f
6 libdispatch.dylib 0x115a624e1 (Missing)
7 libdispatch.dylib 0x115a6354b (Missing)
8 libdispatch.dylib 0x115a65f70 (Missing)
9 libdispatch.dylib 0x115a655dd (Missing)
10 libdispatch.dylib 0x115a72491 (Missing)
11 libdispatch.dylib 0x115a72cfb (Missing)
12 libsystem_pthread.dylib 0x115e49169 (Missing)
13 libsystem_pthread.dylib 0x115e48be9 (Missing)

Relevant Code:

FirebaseApp.configure()