Index: modules/search/search.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/search/search.module,v
retrieving revision 1.303
diff -u -p -r1.303 search.module
--- modules/search/search.module	23 Jul 2009 20:58:26 -0000	1.303
+++ modules/search/search.module	16 Aug 2009 22:46:42 -0000
@@ -1106,6 +1106,17 @@ function search_box(&$form_state, $form_
     '#default_value' => '',
     '#attributes' => array('title' => t('Enter the terms you wish to search for.')),
   );
+  // Add an h2 heading to search_theme_form, not search_block_form which already
+  // get an h2 in block.tpl.php. Headings allow screen-reader and keyboard only
+  // users to navigate to or skip menus and content sections. This heading is
+  // invisible because the search form is visually apparent to sighted users.
+  // See http://www.webaim.org/techniques/css/invisiblecontent/ for information.
+  // Level h2 is appropriate (as opposed to h3 or h4) because, like navigation
+  // menus, the search often precedes or follows the page title or site title h1.
+  // See http://www.w3.org/TR/WCAG-TECHS/H69.html and H42.html for more info.
+  if ($form_id == 'search_theme_form') {
+    $form[$form_id]['#prefix'] = '<h2 class="element-invisible">' . t('Search') . '</h2>';
+  }
   $form['submit'] = array('#type' => 'submit', '#value' => t('Search'));
   $form['#submit'][] = 'search_box_form_submit';