Annotating patches inside diff

I remember that long time ago on git mailing list there was discussed 
extending git-apply and friends (including git-am), to be able to 
ignore lines in patches with selected special prefix, different from 
'@' for chunks headers, ' ' for context, '+'/'-' for added/deleted 
lines.  IIRC it was chose '|' for this purpose.

This way you could annotate patch

@@ -4667,7 +4667,6 @@ HTML
                                  hash_base => $parent_commit);
                print "<td class=\"linenr\">";
                print $cgi->a({ -href => "$blamed#l$orig_lineno",

| moved to <tr>
-                               -id => "l$lineno",
                                -class => "linenr" },
                              esc_html($lineno));
                print "</td>";


Was it accepted or dropped, or is this feature present but not 
documented?
-- 
Jakub Narebski
Poland