Add a menu link using the menu module UI.
integer $plid Parent menu link id.:
string $link Link path.:
string $menu_name Menu name.:
string $weight Menu weight:
array Menu link created.
function addMenuLink($plid = 0, $link = '<front>', $menu_name = 'tools', $expanded = TRUE, $weight = '0') {
  // View add menu link page.
  $this
    ->drupalGet("admin/structure/menu/manage/{$menu_name}/add");
  $this
    ->assertResponse(200);
  $title = '!link_' . $this
    ->randomName(16);
  $edit = array(
    'link_path' => $link,
    'link_title' => $title,
    'description' => '',
    'enabled' => TRUE,
    // Use this to disable the menu and test.
    'expanded' => $expanded,
    // Setting this to true should test whether it works when we do the std_user tests.
    'parent' => $menu_name . ':' . $plid,
    'weight' => $weight,
  );
  // Add menu link.
  $this
    ->drupalPost(NULL, $edit, t('Save'));
  $this
    ->assertResponse(200);
  // Unlike most other modules, there is no confirmation message displayed.
  $this
    ->assertText($title, 'Menu link was added');
  $item = db_query('SELECT * FROM {menu_links} WHERE link_title = :title', array(
    ':title' => $title,
  ))
    ->fetchAssoc();
  $this
    ->assertTrue(t('Menu link was found in database.'));
  $this
    ->assertMenuLink($item['mlid'], array(
    'menu_name' => $menu_name,
    'link_path' => $link,
    'has_children' => 0,
    'plid' => $plid,
  ));
  return $item;
}