Catch Errors when activating a Plugin on register_activation_hook()

gistfile1.txt

function tl_save_error() {
    update_option( 'plugin_error',  ob_get_contents() );
}

add_action( 'activated_plugin', 'tl_save_error' );

/* Then to display the error message: */

echo get_option( 'plugin_error' );