Wordpress - Update post counts (published, draft, unattached) in admin interface

I got this almost working, but refinements are needed to fit the specifics of the question and to deal with Attachments and Post-Types differently (see comments in code)...

---

First, I think it's worth noting how I found the filter:
apply_filters( 'views_' . $screen->id, $views )

• inspect element
  

• do a global search in /wp-admin and /wp-includes for subsubsub (funny class name, btw)...

• and here it is: /wp-admin/includes/class-wp-list-table.php

---

foreach( array( 'edit-post', 'edit-page', 'edit-movie', 'upload' ) as $hook )
    add_filter( "views_$hook" , 'wpse_30331_custom_view_count', 10, 1);

function wpse_30331_custom_view_count( $views ) 
{
    global $current_screen;
    switch( $current_screen->id ) 
    {
        case 'edit-post':
            $views = wpse_30331_manipulate_views( 'post', $views );
            break;
        case 'edit-page':
            $views = wpse_30331_manipulate_views( 'page', $views );
            break;
        case 'edit-movie':
            $views = wpse_30331_manipulate_views( 'movie', $views );
            break;
        case 'upload':
            $views = wpse_30331_manipulate_views( 'attachment', $views );
            break;
    }
    return $views;
}

function wpse_30331_manipulate_views( $what, $views )
{
    global $user_ID, $wpdb;

    /*
     * This is not working for me, 'artist' and 'administrator' are passing this condition (?)
     */
    if ( !current_user_can('artist') ) 
        return $views;

    /*
     * This needs refining, and maybe a better method
     * e.g. Attachments have completely different counts 
     */
    $total = $wpdb->get_var("SELECT COUNT(*) FROM $wpdb->posts WHERE (post_status = 'publish' OR post_status = 'draft' OR post_status = 'pending') AND (post_author = '$user_ID'  AND post_type = '$what' ) ");
    $publish = $wpdb->get_var("SELECT COUNT(*) FROM $wpdb->posts WHERE post_status = 'publish' AND post_author = '$user_ID' AND post_type = '$what' ");
    $draft = $wpdb->get_var("SELECT COUNT(*) FROM $wpdb->posts WHERE post_status = 'draft' AND post_author = '$user_ID' AND post_type = '$what' ");
    $pending = $wpdb->get_var("SELECT COUNT(*) FROM $wpdb->posts WHERE post_status = 'pending' AND post_author = '$user_ID' AND post_type = '$what' ");

    /*
     * Only tested with Posts/Pages
     * - there are moments where Draft and Pending shouldn't return any value
     */
    $views['all'] = preg_replace( '/\(.+\)/U', '('.$total.')', $views['all'] ); 
    $views['publish'] = preg_replace( '/\(.+\)/U', '('.$publish.')', $views['publish'] ); 
    $views['draft'] = preg_replace( '/\(.+\)/U', '('.$draft.')', $views['draft'] ); 
    $views['pending'] = preg_replace( '/\(.+\)/U', '('.$pending.')', $views['pending'] ); 

    // Debug info
    //echo 'Default counts: <pre>'.print_r($views,true).'</pre>';
    //echo '<hr><hr>';
    //echo 'Query for this screen of this post_type: <b>'.$what.'</b><pre>'.print_r($wp_query,true).'</pre>';

    return $views;
}

As of writing, this functionality now resides in the class WP_List_Table, in the method "views()".

The filter now looks like this:

$views = apply_filters( "views_{$this->screen->id}", $views );

$views will contain an array of each list element:

[19-Feb-2016 11:43:44 UTC] Array
(
  [all] => <a href="link_to_view" class="current">Alle <span class="count">(1)</span></a>
  [trash] => <a href="link_to_view">Trash <span class="count">(94)</span></a>
  [confirmed] => <a href="link_to_view">Confirmed <span class="count">(1)</span></a>
)

You can hook it up at the current_screen hook with a priority >10:

add_action( 'current_screen', function ( $current_screen ) {
        if ($current_screen->id === 'edit-my_page')
            add_filter( "views_{$current_screen->id}", 'list_table_views_filter' );
    }, 20);

function list_table_views_filter( array $view ) {
    error_log(print_r($view, true));
    return $view;
}

You can then add/change/remove upon elements in the list.