Clean up some access to null objects in the demo.

just moved stuff around to quiet error messages.
Well, the problem is that some page styles require overlapping of the toolbar (see [here](http://www.google.com/design/spec/layout/structure.html#structure-toolbars), specifically the floating card style). And then there's the complex transition animations from page to page, like [this](http://www.google.com/design/spec/animation/meaningful-transitions.html#meaningful-transitions-visual-continuity).

So that's why I had all the parent swapping. If we can do that with states and transitions, then lets do that. I tend to use the `Behavior on <blah>` style, so I don't know a whole lot about the states/transitions capabilities.