speed functions

<?php
if (function_exists ('add_theme_support')) {
  add_theme_support( 'post-thumbnails' );
  set_post_thumbnail_size(147, 227);
  add_image_size( 'speedmaster_front', '227', '147', false );
  add_image_size( 'speedmaster_other', '383', '205', false );
}

if ( function_exists( 'register_nav_menus' ) ) {
    register_nav_menus(
        array(
            'Main Menu' => 'Header Menu',
        )
    );
}
function new_submenu_class($menu) {
    $menu = preg_replace('/ class="sub-menu"/','/ class="dropdown__container" /',$menu);
    return $menu;
}




add_filter('wp_nav_menu','new_submenu_class');
?>