message: Used final so inner class can reference
  Also got root view instead of content view so it matches the shared element manager
diff: @@ -62,10 +62,11 @@ public class NavigationModule extends ReactContextBaseJavaModule {
  }
  final int enter = this.getAnimationResourceId(enterAnim, this.activityCloseEnterAnimationId);
  final int exit = this.getAnimationResourceId(exitAnim, this.activityCloseExitAnimationId);
  + final boolean backOne = currentCrumb - crumb == 1;
  currentActivity.runOnUiThread(new Runnable() {
  @Override
  public void run() {
  - if (currentCrumb - crumb == 1)
  + if (backOne)
  currentActivity.finishAfterTransition();
  else
  currentActivity.navigateUpTo(intent);
  @@ -86,10 +87,11 @@ public class NavigationModule extends ReactContextBaseJavaModule {
  }
  final int enter = this.getAnimationResourceId(enterAnim, this.activityOpenEnterAnimationId);
  final int exit = this.getAnimationResourceId(exitAnim, this.activityOpenExitAnimationId);
  + final boolean forwardOne = crumb - currentCrumb == 1;
  currentActivity.runOnUiThread(new Runnable() {
  @Override
  public void run() {
  - Pair[] sharedElements = crumb - currentCrumb == 1 ? getSharedElements() : null;
  + Pair[] sharedElements = forwardOne ? getSharedElements() : null;
  if (sharedElements != null) {
  Bundle bundle = ActivityOptions.makeSceneTransitionAnimation(currentActivity, sharedElements).toBundle();
  currentActivity.startActivity(intents[0], bundle);
  @@ -111,7 +113,7 @@ public class NavigationModule extends ReactContextBaseJavaModule {
  @SuppressLint("NewApi")
  private Pair[] getSharedElements() {
  - View rootView = getCurrentActivity().findViewById(android.R.id.content);
  + View rootView = getCurrentActivity().findViewById(android.R.id.content).getRootView();
  HashSet<View> sharedElements = (HashSet<View>) rootView.getTag(R.id.sharedElements);
  if (sharedElements == null)
  return null;
  