Fix fatal, use Message::isDisabled()

Follow-up to dd85e115075661e9e0bb92c7f6d4ab9604efd980 where this issue was
introduced.

Change-Id: I46bd11ca7158d1dec4d8a3533d2607dde9928cc2

diff --git a/includes/SpecialPage.php b/includes/SpecialPage.php
index 6e9df2d..665ca4a 100644 (file)
--- a/includes/SpecialPage.php
+++ b/includes/SpecialPage.php
@@ -980,7 +980,7 @@ abstract class FormSpecialPage extends SpecialPage {
                $form->setWrapperLegendMsg( $this->getMessagePrefix() . '-legend' );
 
                $headerMsg = $this->msg( $this->getMessagePrefix() . '-text' );
-               if ( !$headerMsg->disabled() ) {
+               if ( !$headerMsg->isDisabled() ) {
                        $form->addHeaderText( $headerMsg->parseAsBlock() );
                }