code: public void setProportionalStyle(boolean proportional) {
  
          if (proportional) {
              m_panel.addStyleName(I_CmsInputLayoutBundle.INSTANCE.inputCss().textAreaProportional());
          } else {
              m_panel.removeStyleName(I_CmsInputLayoutBundle.INSTANCE.inputCss().textAreaProportional());
          }
      }
docs: Sets the text area to use a proportional font.<p>
  
  @param proportional <code>true</code> to use a proportional font