rollback method
Rolls this counter's active host transaction back exactly once.
Implementation
void rollback(ChatUtf8LineBudgetCheckpoint checkpoint) {
_requireActiveCheckpoint(checkpoint);
_activeCheckpoints.removeLast();
checkpoint._active = false;
_totalBytes = checkpoint._totalBytes;
_totalLines = checkpoint._totalLines;
_previousWasCR = checkpoint._previousWasCR;
_finished = checkpoint._finished;
_omitted = checkpoint._omitted;
_pendingHighSurrogate = checkpoint._pendingHighSurrogate;
}