code: public TypeInfo registerInnerClass(String simpleName, int accessModifiers) {
      classNames.claimName(simpleName);
      TypeInfo innerClass = outer.innerClass(simpleName);
      innerClassesAccessModifiers.put(innerClass, accessModifiers);
      return innerClass;
    }
docs: Register the given name as an inner class with the given access modifiers.
  
  @return A {@link TypeInfo} with the full class name