message: Get rid of two warnings in the Registry.
  One can be suppressed and is normal in such situations. The other is easy to fix.
diff: @@ -79,7 +79,7 @@ public final class Registry {
  private static final ConcurrentMap<String, Boolean> newKeyAllowedMap =
  new ConcurrentHashMap<>(); // typeUrl -> newKeyAllowed mapping
  - private static final ConcurrentMap<String, Catalogue> catalogueMap =
  + private static final ConcurrentMap<String, Catalogue<?>> catalogueMap =
  new ConcurrentHashMap<>(); // name -> catalogue mapping
  private static final ConcurrentMap<Class<?>, PrimitiveWrapper<?>> primitiveWrapperMap =
  @@ -412,6 +412,7 @@ public final class Registry {
  }
  Class<P> classObject = wrapper.getPrimitiveClass();
  if (primitiveWrapperMap.containsKey(classObject)) {
  + @SuppressWarnings("unchecked") // We know that we only inserted objects of the correct type.
  PrimitiveWrapper<P> existingWrapper =
  (PrimitiveWrapper<P>) (primitiveWrapperMap.get(classObject));
  if (!wrapper.getClass().equals(existingWrapper.getClass())) {
  