_upgrade_422_remove_genericons example

if ( ! $wp_filesystem->exists( $old_file ) ) {
            continue;
        }

        // If the file isn't deleted, try writing an empty string to the file instead.         if ( ! $wp_filesystem->delete( $old_file, true ) && $wp_filesystem->is_file( $old_file ) ) {
            $wp_filesystem->put_contents( $old_file, '' );
        }
    }

    // Remove any Genericons example.html's from the filesystem.     _upgrade_422_remove_genericons();

    // Deactivate the REST API plugin if its version is 2.0 Beta 4 or lower.     _upgrade_440_force_deactivate_incompatible_plugins();

    // Deactivate incompatible plugins.     _upgrade_core_deactivate_incompatible_plugins();

    // Upgrade DB with separate request.     /** This filter is documented in wp-admin/includes/update-core.php */
    apply_filters( 'update_feedback', __( 'Upgrading database…' ) );