Long-term we probably want to pick the render window size and
re-render threshold based on the user's window height instead of
arbitrarily.
When we re-render we probably also want to ensure that the newly
selected message appears in the same location as it would have
before the re-render.
(imported from commit f044b7f2200822e8e6e8dba7108d087a69016134)
By splitting up all_msg_list and home_msg_list, we can properly add/remove
streams from the home view without having to jump through hoops.
(imported from commit 92767197759f7519197dfc58be951b60fa823fbb)
If we have removed a stream from the home view, and our pointer
that we load from the server refers to a message that is no longer
visible, we don't want to error out but rather select the nearest
message to our previously selected one.
(imported from commit d212f1fba7b06836d1d916b43042991625b6f41e)
Messages are now selected on a MessageList, which triggers a
message_selected event that other parts of the code can listen for.
(imported from commit 1da9e4121425c0ac4461b41b7aea169072e1512b)