MC/DC layout bug fix. (#396)

Signed-off-by: Henry Cox <henry.cox@mediatek.com>

Author: henry2cox

bin/genhtml

@@ -11309,8 +11309,12 @@ sub write_source_line(*$$$$$$$)
         if ($mc) {
             # space over far enough to line up with MC/DC extension column
             # remove the span and other HTML
-            (my $s = $br) =~ s/(<\/span>|<span.+?>)//g;
+            my $s = $br;
+            foreach my $tag ('a', 'span') {
+                $s =~ s/(<\/$tag>|<$tag.+?>)//g;
+            }
             $br .= ' ' x ($br_field_width - length($s)) . ' ';
+            die("unexpected lengths") unless $br_field_width >= length($s);
         }
         write_html($handle,
                    "$html_continuation_leader$lineNumSpan" .