fix state restoration

We were getting a new fragment instance to replace our old fragment
instance, but it needed to be reconfigured.

flow/src/main/java/flow/InternalLifecycleIntegration.java

@@ -44,9 +44,11 @@ static void install(Application app, final Activity activity,
       @Override public void onActivityCreated(Activity a, Bundle savedInstanceState) {
         if (a == activity) {
           InternalLifecycleIntegration fragment = find(activity);
-          final boolean newFragment = fragment == null;
+          boolean newFragment = fragment == null;
           if (newFragment) {
             fragment = new InternalLifecycleIntegration();
+          }
+          if (fragment.keyManager == null) {
             fragment.defaultHistory = defaultHistory;
             fragment.parceler = parceler;
             fragment.keyManager = keyManager;