internal_send_message now has the ability to send personals as well as
stream messages.
This change was accidentally lost during a rebase.
(imported from commit 153a3929c5c64be82288293c1f0cc02fcc03c08d)
This allows us to handle the return_messages_immediately part of
get_updates requests without having to talk to the database.
(imported from commit ed0b7742d359efb21a0a4960f4fc25f4337e9ad4)
Tim Abbott
Luke Faraone