title: Spring Boot MVC MessageSource defaultEncoding does not work
body: <p>Simple Spring Boot Web Application.
  Configs snippet:</p>
  
  <pre><code>    @Bean
      public MessageSource validationMessageSource() {
          ReloadableResourceBundleMessageSource messageSource = new ReloadableResourceBundleMessageSource();
          messageSource.setBasename("ValidationMessages");
          messageSource.setDefaultEncoding("UTF-8");
  
          return messageSource;
      }
  
      @Bean
      public Validator validator() {
          LocalValidatorFactoryBean localValidatorFactoryBean = new LocalValidatorFactoryBean();
          localValidatorFactoryBean.setValidationMessageSource(validationMessageSource());
          return localValidatorFactoryBean;
      }
  </code></pre>
  
  <p>I set a <code>defaultEncoding</code> as <code>UTF-8</code> . I have <code>ValidationMessages.properties</code> file that is encoded in UTF-8 (my IntelliJ says so, notepad++ says so) and contains different characters.</p>
  
  <p>I have a simple web page (created using Freemarker). There is some static UTF-8 text on that page and it is displayed correctly.</p>
  
  <p>And I want to see correct error messages when I submit a form located on that page, but when validation fails ( JSR-303/JSR-349 validation) I can see someting like <code>Ð¾Ð±Ð¾Ð²ÑÐ·ÐºÐ¾Ð²Ðµ Ð¿Ð¾Ð»Ðµ. min 2, max 15 ÑÐ¸Ð¼Ð²Ð¾Ð»ÑÐ²</code> that's a message from <code>.properties</code> but it's wrongly encoded!</p>
  
  <p>Here is the page (simplified: no divs, css , js, etc.):</p>
  
  <pre><code>&lt;#import "/spring.ftl" as spring/&gt;
  &lt;!DOCTYPE html&gt;
  &lt;html lang="en"&gt;
      &lt;head&gt;
          &lt;title&gt;ShareMyCar&lt;/title&gt;
          &lt;meta charset="utf-8"&gt;
          &lt;meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no"&gt;
  
      &lt;/head&gt;
      &lt;body&gt;
         &lt;form action="/registration" method="POST"&gt;
             &lt;@spring.formInput path="modelObj.name" /&gt;
             &lt;@spring.showErrors "&lt;br&gt;"/&gt;
  
             &lt;input type="submit" class="btn btn-primary" value="Submit" /&gt;            
          &lt;/form&gt;
  
      &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>What else I need to do to make it work?</p>