code: public static FieldScope allowingFieldDescriptors(
        FieldDescriptor firstFieldDescriptor, FieldDescriptor... rest) {
      return FieldScopeImpl.createAllowingFieldDescriptors(asList(firstFieldDescriptor, rest));
    }
docs: Returns a {@link FieldScope} which matches nothing except the provided field descriptors for
  the message.
  
  @see FieldScope#allowingFieldDescriptors(FieldDescriptor, FieldDescriptor...)