jQuery-UI style conflict

If a jQuery UI stylesheet is loaded in the WordPress admin, the color picker looks broken. 

See screenshot.
![image](https://f.cloud.github.com/assets/494927/1546524/4f796f36-4d87-11e3-8eb2-6ee0e5fcb03b.png)

To reproduce on the theme customizer page use the following code: 

    add_action( 'customize_controls_print_styles', function() {
        wp_enqueue_style( 'jquery-ui-theme', 'http://ajax.googleapis.com/ajax/libs/jqueryui/1.10.3/themes/smoothness/jquery-ui.min.css' );
    }, 100 );

To fix this, the color picker should override the default jQuery-UI styles.