title: render a SINGLE GSP in a specific locale
body: <p>I'm trying to render a GSP in a specific locale.</p>
  
  <p>Both these solutions work</p>
  
  <p>using params</p>
  
  <pre><code>    /book/list?lang=es
  </code></pre>
  
  <p>Using code in controller</p>
  
  <pre><code>    def newLocale = new Locale(lang)
      RCU.getLocaleResolver(request).setLocale(request, response, newLocale)
      render(view: "mail", model: [invoiceInstance: invoiceInstance])
  </code></pre>
  
  <p>Unfortunately both these solution change the session object forever and affects all GSP afterwards.</p>
  
  <p>If I try the change the LocaleResolver after the Render statement it does not work.</p>
  
  <pre><code>    // Switch to OWNER language for print preview
      def newLocale = new Locale(lang)
      RCU.getLocaleResolver(request).setLocale(request, response, newLocale)
  
      render(view: "mail", model: [invoiceInstance: invoiceInstance])
  
      // switch back to user language
      def newLocale2 = new Locale(user.language)
      RCU.getLocaleResolver(request).setLocale(request, response, newLocale2) 
  </code></pre>
  
  <p>So how can a force a SINGLE render in a specific locale?</p>