* In most cases, eslint --fix with the right comma-dangle settings was
able to update the code correctly.
* The exceptions were cases where the parser incorrectly treated the
arguments to functions like `assert_equal` as arguments; we fixed
these manually. Since this is test code, we can be reasonably
confident that just fixing the failures suffices to correct any bugs
introduced by making changes automatically.
The widget that gets built in topic_list.build_widget()
now knows how to add itself to its parent element and expose
an interface to retrieve the parent.
This moves one method over from stream_list.js. There's still a
lot of boilerplate here, unfortunately, as topic lists have a lot
of dependencies on other parts of the system--narrowing state,
muting state, jQuery, handlebars, etc.