Adds plugin and theme links to the Network Admin section of the admin menu bar

add-plugins-link.php

<?php
/*
Plugin Name: Add Plugins Link
Description: Adds plugin and theme links to the Network Admin section of the admin menu bar.
Author: Stephanie Leary
Version: 1.0
Author URI: http://stephanieleary.com
*/

add_action('admin_bar_menu', 'add_plugins_link_for_superadmins', 25);
function add_plugins_link_for_superadmins() {	
	global $wp_admin_bar;  
        if ( !is_user_logged_in() ) { return; }  
        if ( !is_super_admin() || !is_admin_bar_showing() ) { return; }

	global $blog_id;

	$user = get_current_user_id();
	if (is_super_admin( $user )) {
  	
		if ( function_exists('is_multisite') && is_multisite() ) {
	        $themes =  network_admin_url( 'themes.php' );
			$plugins = network_admin_url( 'plugins.php' );
		}
	    else {
	        $themes = admin_url( 'themes.php' );
			$plugins = admin_url( 'plugins.php' );
		}
		$wp_admin_bar->add_menu( array(  
			'parent' => 'network-admin',
	        'id' => 'themes',  
	        'title' => __('Themes'),  
	        'href' => $themes )  
	    );
		$wp_admin_bar->add_menu( array( 
			'parent' => 'network-admin', 
	        'id' => 'plugins',  
	        'title' => __('Plugins'),  
	        'href' => $plugins )  
	    );
	}
}