Most of this was straightforward.
Most functions that were grabbed verbatim and whole from
the original class still have one-line wrappers.
Many functions are just-the-data versions of functions that
remain in MessageList: see add, append, prepend, remove as
examples. In a typical pattern the MessageList code becomes
super simple:
prepend: function MessageList_prepend(messages) {
var viewable_messages = this.data.prepend(messages);
this.view.prepend(viewable_messages);
},
Two large functions had some minor surgery:
triage_messages =
top half of add_messages +
API to pass three lists back
change_message_id =
original version +
two simple callbacks to list
For the function update_muting_and_rerender(), we continue
to early-exit if this.muting_enabled is false, and we copied
that same defensive check to the new function
named update_items_for_muting(), even though it's technically
hidden from that codepath by the caller.
