title: addArgumentResolver not being invoked in config class
body: <p>I have a config class with <code>@EnableMVC</code> and <code>Configuration</code> annotations. I have extended the <code>WebMvcConfigurerAdapter</code> class and overridden the <code>addArgumentResolver</code> method to add one. However that method is never getting called. I have done a system output to test whether it gets invoked or not. Strangely, I tried overriding the <code>addInterceptor</code> method to the same class and it gets invoked just fine. Any clue to what is happening here would be apprecitated.</p>
  
  <pre><code>@Configuration
  @ComponentScan("com.fico.cardinal")
  @EnableWebMvc
  public class WebContextConfig extends WebMvcConfigurerAdapter {
  @Bean
  public ValidateJson validateJson() {
      System.out.println("Created bean validate json");
      return new ValidateJson();
  }
  
  @Bean
  private RequestMappingHandlerAdapter requestMappingHandlerAdapter() {
      return new RequestMappingHandlerAdapter();
  } 
  
  @Bean
  public ValidateJsonSchema validateJsonSchema() {
      System.out.println("Created bean validate json schema");
      return new ValidateJsonSchema();
  }
  
  @Override
  public void addArgumentResolvers(
          List&lt;HandlerMethodArgumentResolver&gt; argumentResolvers) {
      super.addArgumentResolvers(argumentResolvers);
      argumentResolvers.add(validateJsonSchema());
      System.out.println("Added resolver");
      // doesn't gets called
  }
  
  @Override
  public void addInterceptors(InterceptorRegistry registry) {
      super.addInterceptors(registry);
      registry.addInterceptor(validateJson());
      System.out.println("added interceptor");
      // gets called
  }
  </code></pre>
  
  <p>Edit: Included the complete config class</p>