markNudgeScreenExit method
Marks the nudge's close as a screen exit. Only setCurrentScreen calls it, when the active campaign no longer targets the new screen.
Implementation
void markNudgeScreenExit(String campaignId) {
_pendingNudgeDismissCampaignId = campaignId;
_pendingNudgeDismissReason = DismissReason.screenExit;
}