message: Swtiched a and b around in a.equals(b)
  Avoids java nullpointerexception warning
diff: @@ -159,8 +159,7 @@ public class NavigationStackView extends ViewGroup {
  }
  currentActivity.overridePendingTransition(enter, exit);
  }
  - if (crumb == currentCrumb) {
  - if (keys.getString(crumb) != null && !keys.getString(crumb).equals(oldKey)) {
  + if (crumb == currentCrumb && !oldKey.equals(keys.getString(crumb))) {
  Intent intent = new Intent(getContext(), SceneActivity.getActivity(crumb));
  String key = keys.getString(crumb);
  intent.putExtra(SceneActivity.KEY, key);
  @@ -170,7 +169,6 @@ public class NavigationStackView extends ViewGroup {
  currentActivity.startActivity(intent);
  currentActivity.overridePendingTransition(enter, exit);
  }
  - }
  oldCrumb = keys.size() - 1;
  oldKey = keys.getString(oldCrumb);
  }
  