Wrong order of arguments in call_user_func() for Walker_Comment::start_el()

[milana_cap]

Arguments order for rendering all types of comments is $comment, $depth, $args except for the custom callback:

call_user_func( $args['callback'], $comment, $args, $depth );

This causes every custom callback to throw an error when you use $args and $depth as you'd expect.

For example, comment_reply_link() inside callback can not be used like it's suppose to be used, like so:

<?php
comment_reply_link( array_merge( $args, array(
        'add_below' => 'div-comment',
        'depth'     => $depth,
        'max_depth' => $args['max_depth'],
        'before'    => '<div class="reply">',
        'after'     => '</div>'
) ) );

You need to replace $depth and $args, like so:

<?php
comment_reply_link( array_merge( $depth, array(
        'add_below' => 'div-comment',
        'depth'     => $args,
        'max_depth' => $depth['max_depth'],
        'before'    => '<div class="reply">',
        'after'     => '</div>'
) ) );

[pento]

Patch needs review, particularly with consideration to if it's likely to break workarounds for this bug.

Unit tests would also be good.

Trac ticket: https://core.trac.wordpress.org/ticket/45498