Transfer VM fragment logic to presenter.

We want the presenter to handle/manage resources pertinent to
the activity lifecycle, so that we can convert the playback
fragment into a component.

My apologies to whoever has to disentangle this presenter logic
later (though that could be me).

Bug: 21170557
Change-Id: Icf65d3c23f1a12a7d63c2a281f96d2168a4a560f