Add the EventTracker extension for cleaning evts

Add the EventTracker extension for cleaning evts

- Add the new extension and tests to track/clean up events created during an
instance.
- Updated any objects using _events to use the new Extension
- A couple of places touched _events directly for tests/etc. This was left for
now.

https://code.launchpad.net/~rharding/juju-gui/event_tracker/+merge/157750

(do not edit description out of merge proposal)

[rharding, 2013-04-08 20:51:50]

Please take a look.

[jeff.pihach, 2013-04-09 14:21:41]

LGTM - Thanks for finally putting together a formalized way of doing this :) I
have just a few cleanup comments below that I'd like to have done before
landing.

https://codereview.appspot.com/8491045/diff/1/app/assets/javascripts/event-tr...
File app/assets/javascripts/event-tracker.js (right):

https://codereview.appspot.com/8491045/diff/1/app/assets/javascripts/event-tr...
app/assets/javascripts/event-tracker.js:9: * var XX = Y.Base.create('xxx',
Y.Base, [Y.event.EventTracker]...)
typo on Y.event

https://codereview.appspot.com/8491045/diff/1/app/assets/javascripts/event-tr...
app/assets/javascripts/event-tracker.js:40: this.on('destroy',
this._destroyEvents, this);
This event should probably be tracked. But in a separate super private so that
you can detach all of the events on a whim but still leave this one - One of the
files would use this technique in this branch.

https://codereview.appspot.com/8491045/diff/1/app/assets/javascripts/event-tr...
app/assets/javascripts/event-tracker.js:52: _destroyEvents: function() {
should probably be called _detachEvents

https://codereview.appspot.com/8491045/diff/1/app/assets/javascripts/event-tr...
app/assets/javascripts/event-tracker.js:65: evt: function(handler) {
should probably be called trackEvent() or saveHandler() or something a little
more descriptive.

https://codereview.appspot.com/8491045/diff/1/app/widgets/charm-search.js
File app/widgets/charm-search.js (right):

https://codereview.appspot.com/8491045/diff/1/app/widgets/charm-search.js#new...
app/widgets/charm-search.js:19: console.log('tracker', Y.Event.EventTracker);
These logs probably shouldnt' be committed.

https://codereview.appspot.com/8491045/diff/1/app/widgets/charm-token.js
File app/widgets/charm-token.js (right):

https://codereview.appspot.com/8491045/diff/1/app/widgets/charm-token.js#newc...
app/widgets/charm-token.js:37: * tracker because we want to be able to rebind
things.
I would access the extensions detach method here.

[j.c.sackett, 2013-04-09 14:34:00]

LGTM - a bit of bikeshedding and questions.

https://codereview.appspot.com/8491045/diff/1/app/assets/javascripts/event-tr...
File app/assets/javascripts/event-tracker.js (right):

https://codereview.appspot.com/8491045/diff/1/app/assets/javascripts/event-tr...
app/assets/javascripts/event-tracker.js:25: ns.EventTracker = function() {
Granted this is bikeshedding, but there are similar objects to this in YUI
already named *Manager; given that, EventManager feels like a better name to me.

https://codereview.appspot.com/8491045/diff/1/app/assets/javascripts/event-tr...
app/assets/javascripts/event-tracker.js:66: this._events.push(handler);
add* seems to be the normal naming convention for things like this (e.g.
attribute manager's have addAttr). I think this should be addEvent

https://codereview.appspot.com/8491045/diff/1/app/widgets/charm-token.js
File app/widgets/charm-token.js (right):

https://codereview.appspot.com/8491045/diff/1/app/widgets/charm-token.js#newc...
app/widgets/charm-token.js:38: *
I won't assert what's right here, but I'm curious as well why you can't just use
the EventTracker's detaching method? If you did, I don't think you even need the
comment explaining why, since the following method is the bindUI showing unbind
called outside of destroy.

[rharding, 2013-04-09 17:07:51]

*** Submitted:

Add the EventTracker extension for cleaning evts

- Add the new extension and tests to track/clean up events created during an
instance.
- Updated any objects using _events to use the new Extension
- A couple of places touched _events directly for tests/etc. This was left for
now.

R=jeff.pihach, j.c.sackett
CC=
https://codereview.appspot.com/8491045