lp.bugs.buglisting.TableView needs tests

[Deryck Hodge]

lp.bugs.buglisting.TableView was created as an integration point for all the js objects hooked up in custom bug listings. It was added to be able to pull some untested js from a template, but was itself added without tests. This object needs to have tests added for it. It will be a bit of work to get these tests added now, since the object was created without tests first. It doesn't seem obviously testable at first glance, and needs some refactoring to make it more easily testable. At the very least, we need a little unit test to verify TableView's methods.