Here are the functions in top_left_corner:
get_global_filter_li: pure code move
update_count_in_dom: simplifed copy of similar function in stream_list.js
update_dom_with_unread_counts: pure code move, split out from function
of same name in stream_list.js
delselect_top_left_corner_items: pure code move
handle_narrow_activated: pure code move + rename
handle_narrow_deactivated: pure code move, split out from from function
of smae name in stream_list.js
Steve Howell