Defer sorting opened messages to their new position in the message list

For the last N displayed messages we remember the original 'read' and 'starred' state of the messages. We pass this information to `MessageListLoader` so messages can be sorted according to these remembered values and not the current state. This way messages, that are marked as read/unread or starred/not starred while being displayed, won't immediately change position in the message list if the list is sorted by these fields.
The main benefit is that the swipe to next/previous message feature will work in a less surprising way.