message: Simplified previous state and data parsing
diff: @@ -5,9 +5,8 @@ import PhotoZoom from './PhotoZoom';
  export default () => (
  <NavigationMotion
  unmountedStyle={(state, data, crumbs) => {
  - var previousCrumb = crumbs[crumbs.length - 1];
  - var fromSameTweet = previousCrumb && previousCrumb.state.key === 'tweet' && previousCrumb.data.id === data.id;
  - var sharePhoto = state.key === 'photo' && !fromSameTweet;
  + var { state: previousState, data: previousData } = crumbs[crumbs.length - 1] || {};
  + var sharePhoto = state.key === 'photo' && !(previousState.key === 'tweet' && previousData.id === data.id);
  return !sharePhoto ? {translate: 100, scale: 1, opacity: 1} : {translate: 0, scale: 1, opacity: 0};
  }}
  mountedStyle={{translate: 0, scale: 1, opacity: 1}}
  