[bug?] Component onUpdate methods not always being fired.

This has happened in several times to me already, with versions of Famous Engine ranging from 0.5 to 0.7.2, but I'm not at all sure what I have to do prior in order to experience the problem. I have some code like this:

``` js
...
this._positionTransitionable = new Transitionable(0)
this._positionTransitionable.set(200, {duration: 600, curve: 'easeOut'})
let self = this
console.log('node?', node) // node exists, and is a Node
self._goForwardAnimation = node.addComponent({
onUpdate() {
console.log('animating forward') // never fires
if (self._positionTransitionable.isActive()) {
let position = node.getPosition()
node.setPosition(position[0], position[1], self._positionTransitionable.get())
node.requestUpdateOnNextTick(self._goForwardAnimation)
}
else { // clean up.
console.log('Getting rid of the component.')
node.removeComponent(self._goForwardAnimation)
}
}
})
node.requestUpdateOnNextTick(self._goForwardAnimation)
...
```

The expected behavior is that the `_goForwardAnimation` will start updating after being started with `node.requestUpdateOnNextTick`, but it doesn't happen. The `console.log` inside the component never fires.