Remove over-aggressive assert.
Remove over-aggressive assert.

closeWithFinalState: assumes delegate != nil, but that is not true if when
startWithdelegate: was called we entered backoff (performBackoffWithDelegate:)
and so self.delegate did not get assigned yet.

We could rework the code to make the assertion hold, but per offline
discussion this assert doesn't represent an invariant that we care about
and so I'm just removing it.

firebase/firebase-ios-sdk,firebase/firebase-ios-sdk,firebase/firebase-ios-sdk,firebase/firebase-ios-sdk,firebase/firebase-ios-sdk,firebase/firebase-ios-sdk,firebase/firebase-ios-sdk