E_ALL Compliance: Fix a couple of notices in theme_links()

In includes/theme.inc, theme_links() produces

Notice: Undefined index: query in c:\program files\apache group\apache\htdocs\drupalhead\includes\theme.inc on line 534
Notice: Undefined index: fragment in c:\program files\apache group\apache\htdocs\drupalhead\includes\theme.inc on line 534

The offending line:

        $output .= l($link['title'], $link['href'], $link['attributes'], $link['query'], $link['fragment']);

may be called with $link['query'] and/or $link['fragment'] unset. (Maybe also attributes too?). The link function l() defaults to NULL if query and fragment are not supplied (which is luckily what you get from an undefined value anyway), so we can fix this without changing the logic to:

        $output .= l($link['title'], $link['href'], $link['attributes'], isset($link['query']) ? $link['query'] : NULL, 
                      isset($link['fragment']) ? $link['fragment'] : NULL);

The attached patch fixes this line. Mark.

PS I hope these are useful, but do stop me if this is becoming silly...