title: How to define state when using `history.goBack()`
body: <p>I've created some animations that I'd like to use for navigating between routes in my application.  I have a back button visible on certain pages that allows the users to pop off the navigation stack to access the most recent page.  I'd like two different animations, one for navigating deeper in the stack and one for popping back to the most recent page.
  I'd like to use <code>history.goBack()</code>, but there seems to be no way to pass a state and thus use a different animation.</p>
  
  <p>I used this <a href="https://medium.com/lalilo/dynamic-transitions-with-react-router-and-react-transition-group-69ab795815c9" rel="noreferrer">article</a> to figure out how to have dynamic animations for my components, but unless I use <code>history.push({pathname, state:{animation, duration}})</code> I don't see how I can specify a different animation to use when a user goes back.</p>