Fix for scheduling from message list; another attempt at fixing drafts folder corruption

When the user selects one or more messages in the messages list and then uses the "Schedule message(s)" menu command, fill in the pop-up window properly with the default send time.

Increase the compact delay after scheduling, intended to avoid Drafts folder corruption, from 1 second to 2 seconds, because apparently 1 second isn't long enough. I don't know for certain that this change will work but I need to get it out into the world to collect more data about it.

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