void QuotaManager::NotifyOriginNoLongerInUse(const GURL& origin) {
  DCHECK(io_thread_->BelongsToCurrentThread());
  DCHECK(IsOriginInUse(origin));
  int& count = origins_in_use_[origin];
  if (--count == 0)
    origins_in_use_.erase(origin);
}
