WP_Customize_Nav_Menus::available_item_types

					new WP_Customize_Nav_Menu_Item_Control(
						$this->manager,
						$menu_item_setting_id,
						array(
							'label'    => $item->title,
							'section'  => $section_id,
							'priority' => 10 + $i,
						)
					)
				);
			}

			// Note: other controls inside of this section get added dynamically in JS via the MenuSection.ready() function.
		}

		// Add the add-new-menu section and controls.
		$this->manager->add_section(
			'add_menu',
			array(
				'type'     => 'new_menu',
				'title'    => __( 'New Menu' ),
				'panel'    => 'nav_menus',
				'priority' => 20,
			)
		);

		$this->manager->add_setting(
			new WP_Customize_Filter_Setting(
				$this->manager,
				'nav_menus_created_posts',
				array(
					'transport'         => 'postMessage',
					'type'              => 'option', // To prevent theme prefix in changeset.
					'default'           => array(),
					'sanitize_callback' => array( $this, 'sanitize_nav_menus_created_posts' ),
				)
			)
		);
	}

	/**
	 * Get the base10 intval.