Fix some rare crashes when restoring the app after termination

Also fixes an issue where the app shortcuts would not work for unencrypted vaults

app/src/main/java/com/beemdevelopment/aegis/ui/PreferencesFragment.java

@@ -339,6 +339,11 @@ public class PreferencesFragment extends PreferenceFragmentCompat {
                 return true;
             }
         });
+    }
+
+    @Override
+    public void onActivityCreated (Bundle savedInstanceState) {
+        super.onActivityCreated(savedInstanceState);
         updateEncryptionPreferences();
     }