This patch does nothing but rename a pair of variables:
"prevState/state" becomes "oldState/newState". Reasoning:
1. The abbreviated "prev" is confusing, especially because we
are in a codebase that is all about "previews".
2. We are in a context that is all about a state **change**.
Change listeners get notified about the change from one state
to another. While it would be possible to stick to the already
mentioned "previous/current" terminology, I find the word
"current" confusing. What is "current" in this context? Did
the state already change? Am I notified about a change that is
**going** to happen or already happened? Is this even relevant?
I don't think it is. Therefor "old/new".
Another possibility is "previous/next".
Change-Id: Id886e1a095967fe86fb9021f59e335c62da8994e
