issue: ENG-5766
MessageStore looks like this:
export type MessageStore = { +messages: { +[id: string]: RawMessageInfo }, +threads: MessageStoreThreads, +local: { +[id: string]: LocalMessageInfo }, +currentAsOf: { +[keyserverID: string]: number }, };
messages, local and threads are filtered by updateMessageStoreWithLatestThreadInfos/processMessageStoreOperations based on what threads were removed by thread reducer. I only need to update currentAsOf.