Make single widget area top level in 4.0 Customize Panel

Got it.

Admittedly, this feels hacky but seems to do the job just fine.

In my existing customize_register hook I set the following:

// Retreive the widget section in the Theme Customizer
// We need to cast the return of get_section to an object
// "the_widgets_section" in get_section is the ID of the registered widget area
$widget_area = (object) $wp_customize->get_section( 'sidebar-widgets-the_widgets_section' )
// The value of panel will be 'widgets', so we set it back to '' (top level panel)
$widget_area->panel="";
// If you're so inclined, we can change the title of it as well.
$widget_area->title = __( 'My Widgets', 'textdomain' );